diff --git a/tests/wpt/metadata/FileAPI/url/url-with-fetch.any.js.ini b/tests/wpt/metadata/FileAPI/url/url-with-fetch.any.js.ini
index abf0d50aff3..4c1aa18e695 100644
--- a/tests/wpt/metadata/FileAPI/url/url-with-fetch.any.js.ini
+++ b/tests/wpt/metadata/FileAPI/url/url-with-fetch.any.js.ini
@@ -2,6 +2,9 @@
   [Revoke blob URL after creating Request, will fetch]
     expected: FAIL
 
+  [Revoke blob URL after calling fetch, fetch should succeed]
+    expected: FAIL
+
 
 [url-with-fetch.any.html]
   [Revoke blob URL after creating Request, will fetch]
diff --git a/tests/wpt/metadata/MANIFEST.json b/tests/wpt/metadata/MANIFEST.json
index 4ff61c1c047..a6e8353e8bf 100644
--- a/tests/wpt/metadata/MANIFEST.json
+++ b/tests/wpt/metadata/MANIFEST.json
@@ -123533,6 +123533,18 @@
      {}
     ]
    ],
+   "css/css-flexbox/percentage-heights-010.html": [
+    [
+     "css/css-flexbox/percentage-heights-010.html",
+     [
+      [
+       "/css/reference/ref-filled-green-100px-square.xht",
+       "=="
+      ]
+     ],
+     {}
+    ]
+   ],
    "css/css-flexbox/percentage-size-subitems-001.html": [
     [
      "css/css-flexbox/percentage-size-subitems-001.html",
@@ -216432,6 +216444,9 @@
    "2dcontext/imagebitmap/common.sub.js": [
     []
    ],
+   "2dcontext/imagebitmap/createImageBitmap-worker.js": [
+    []
+   ],
    "2dcontext/imagebitmap/transfer-worker.js": [
     []
    ],
@@ -280488,6 +280503,9 @@
    "interfaces/mst-content-hint.idl": [
     []
    ],
+   "interfaces/native-file-system.idl": [
+    []
+   ],
    "interfaces/navigation-timing.idl": [
     []
    ],
@@ -283089,6 +283107,33 @@
    "quirks/unitless-length/support/common.js": [
     []
    ],
+   "referrer-policy/4K+1/generic/spec_json.js": [
+    []
+   ],
+   "referrer-policy/4K+1/generic/test-case.sub.js": [
+    []
+   ],
+   "referrer-policy/4K+1/spec.src.json": [
+    []
+   ],
+   "referrer-policy/4K-1/generic/spec_json.js": [
+    []
+   ],
+   "referrer-policy/4K-1/generic/test-case.sub.js": [
+    []
+   ],
+   "referrer-policy/4K-1/spec.src.json": [
+    []
+   ],
+   "referrer-policy/4K/generic/spec_json.js": [
+    []
+   ],
+   "referrer-policy/4K/generic/test-case.sub.js": [
+    []
+   ],
+   "referrer-policy/4K/spec.src.json": [
+    []
+   ],
    "referrer-policy/META.yml": [
     []
    ],
@@ -300134,6 +300179,12 @@
      {}
     ]
    ],
+   "2dcontext/imagebitmap/createImageBitmap-in-worker-transfer.html": [
+    [
+     "2dcontext/imagebitmap/createImageBitmap-in-worker-transfer.html",
+     {}
+    ]
+   ],
    "2dcontext/imagebitmap/createImageBitmap-invalid-args.html": [
     [
      "2dcontext/imagebitmap/createImageBitmap-invalid-args.html",
@@ -365329,6 +365380,12 @@
      {}
     ]
    ],
+   "html/semantics/document-metadata/the-style-element/style_load_event.html": [
+    [
+     "html/semantics/document-metadata/the-style-element/style_load_event.html",
+     {}
+    ]
+   ],
    "html/semantics/document-metadata/the-style-element/style_media.html": [
     [
      "html/semantics/document-metadata/the-style-element/style_media.html",
@@ -382425,6 +382482,38 @@
      }
     ]
    ],
+   "native-file-system/idlharness.https.any.js": [
+    [
+     "native-file-system/idlharness.https.any.html",
+     {
+      "script_metadata": [
+       [
+        "script",
+        "/resources/WebIDLParser.js"
+       ],
+       [
+        "script",
+        "/resources/idlharness.js"
+       ]
+      ]
+     }
+    ],
+    [
+     "native-file-system/idlharness.https.any.worker.html",
+     {
+      "script_metadata": [
+       [
+        "script",
+        "/resources/WebIDLParser.js"
+       ],
+       [
+        "script",
+        "/resources/idlharness.js"
+       ]
+      ]
+     }
+    ]
+   ],
    "native-file-system/opaque-origin.https.window.js": [
     [
      "native-file-system/opaque-origin.https.window.html",
@@ -393793,9 +393882,9 @@
      {}
     ]
    ],
-   "payment-request/onpaymentmenthodchange-attribute.https.html": [
+   "payment-request/onpaymentmethodchange-attribute.https.html": [
     [
-     "payment-request/onpaymentmenthodchange-attribute.https.html",
+     "payment-request/onpaymentmethodchange-attribute.https.html",
      {}
     ]
    ],
@@ -429413,6 +429502,78 @@
      }
     ]
    ],
+   "wasm/jsapi/table/grow-reftypes.tentative.any.js": [
+    [
+     "wasm/jsapi/table/grow-reftypes.tentative.any.html",
+     {
+      "script_metadata": [
+       [
+        "global",
+        "jsshell"
+       ],
+       [
+        "script",
+        "assertions.js"
+       ],
+       [
+        "script",
+        "/wasm/jsapi/wasm-constants.js"
+       ],
+       [
+        "script",
+        "/wasm/jsapi/wasm-module-builder.js"
+       ]
+      ]
+     }
+    ],
+    [
+     "wasm/jsapi/table/grow-reftypes.tentative.any.js",
+     {
+      "jsshell": true,
+      "script_metadata": [
+       [
+        "global",
+        "jsshell"
+       ],
+       [
+        "script",
+        "assertions.js"
+       ],
+       [
+        "script",
+        "/wasm/jsapi/wasm-constants.js"
+       ],
+       [
+        "script",
+        "/wasm/jsapi/wasm-module-builder.js"
+       ]
+      ]
+     }
+    ],
+    [
+     "wasm/jsapi/table/grow-reftypes.tentative.any.worker.html",
+     {
+      "script_metadata": [
+       [
+        "global",
+        "jsshell"
+       ],
+       [
+        "script",
+        "assertions.js"
+       ],
+       [
+        "script",
+        "/wasm/jsapi/wasm-constants.js"
+       ],
+       [
+        "script",
+        "/wasm/jsapi/wasm-module-builder.js"
+       ]
+      ]
+     }
+    ]
+   ],
    "wasm/jsapi/table/grow.any.js": [
     [
      "wasm/jsapi/table/grow.any.html",
@@ -434304,6 +434465,12 @@
      }
     ]
    ],
+   "webrtc-extensions/RTCRtpParameters-maxFramerate.html": [
+    [
+     "webrtc-extensions/RTCRtpParameters-maxFramerate.html",
+     {}
+    ]
+   ],
    "webrtc-extensions/RTCRtpReceiver-playoutDelayHint.html": [
     [
      "webrtc-extensions/RTCRtpReceiver-playoutDelayHint.html",
@@ -468917,6 +469084,10 @@
    "bbc920f1e303ff45e22c4396d098decafffac87b",
    "testharness"
   ],
+  "2dcontext/imagebitmap/createImageBitmap-in-worker-transfer.html": [
+   "727a8a4978db6ea62451d8af642a91d57b0aaed6",
+   "testharness"
+  ],
   "2dcontext/imagebitmap/createImageBitmap-invalid-args.html": [
    "c200ce36f98658ef0dae6f654f892105a7e7aca1",
    "testharness"
@@ -468937,6 +469108,10 @@
    "708f97097c16e9074cc3cbf54dad0ee75df7967c",
    "testharness"
   ],
+  "2dcontext/imagebitmap/createImageBitmap-worker.js": [
+   "67a0904e479323e4a159937f49919580109fbc61",
+   "support"
+  ],
   "2dcontext/imagebitmap/transfer-worker.js": [
    "55465a899ca27d5202dfa796ec5200bde845892b",
    "support"
@@ -471270,7 +471445,7 @@
    "testharness"
   ],
   "IndexedDB/idb-binary-key-detached.htm": [
-   "26afcfb1cd03c2cfb3e4fcc4a9ce382144225f24",
+   "5a2e1f79f42e5d816870a1f948519317f0fd00fe",
    "testharness"
   ],
   "IndexedDB/idb-binary-key-roundtrip.htm": [
@@ -471298,7 +471473,7 @@
    "testharness"
   ],
   "IndexedDB/idbcursor-advance-exception-order.html": [
-   "13f7fdae5a57a716a13ed808fcd3613034f71e2d",
+   "1e05c9074d6b1e5c86c46cc1f91bdbd0ecb26ad9",
    "testharness"
   ],
   "IndexedDB/idbcursor-advance-invalid.htm": [
@@ -472026,7 +472201,7 @@
    "testharness"
   ],
   "IndexedDB/idbkeyrange-includes.htm": [
-   "aea588051aeaab63c3855a778b22d1a6932d78ff",
+   "9a408e888a42d2f79eaf2ed2f30311fbaa596625",
    "testharness"
   ],
   "IndexedDB/idbkeyrange.htm": [
@@ -476666,7 +476841,7 @@
    "testharness"
   ],
   "bluetooth/idl/idl-BluetoothUUID.html": [
-   "2adf35a419ff9687511884e4294ec72dbb22d347",
+   "14463127e06b422a2830042bb887e5108e200753",
    "testharness"
   ],
   "bluetooth/idl/idl-NavigatorBluetooth.html": [
@@ -477746,7 +477921,7 @@
    "support"
   ],
   "common/security-features/README.md": [
-   "2509d661b4afb68a5bfca0a41270d93586ddbe49",
+   "46cabd2bb3c24dd94f81e78a7799512e7741cd13",
    "support"
   ],
   "common/security-features/resources/common.sub.js": [
@@ -477866,11 +478041,11 @@
    "support"
   ],
   "common/security-features/tools/format_spec_src_json.py": [
-   "b4549bb710cd119e87ca4a41d65d7980b6b40406",
+   "d1bf5817ad208f3ae8cc16b3ad11cc0d310d35aa",
    "support"
   ],
   "common/security-features/tools/generate.py": [
-   "ba997067b3f44640fec79fac9cea10a79ae982af",
+   "3345d6520691de734977a18d73c94f71b446408a",
    "support"
   ],
   "common/security-features/tools/spec_validator.py": [
@@ -477886,11 +478061,11 @@
    "support"
   ],
   "common/security-features/tools/template/test.debug.html.template": [
-   "b4b0fec733e1ce6f6a5cad0f9c9d4391aa244fb1",
+   "f09395cff49a7a4282606a79135b813354e14022",
    "support"
   ],
   "common/security-features/tools/template/test.release.html.template": [
-   "d93506e231a4c6e719b055b1e312bd163eb9519d",
+   "6bf79f77df1a6a3d357b68d1f59f90e04ca0815f",
    "support"
   ],
   "common/security-features/tools/util.py": [
@@ -477918,7 +478093,7 @@
    "support"
   ],
   "common/test-setting-immutable-prototype.js": [
-   "92e61c07424166f4fd514ac0cd6d50f1c68b0020",
+   "de619b1d76663d0f41f13b720609bd4cc28747c2",
    "support"
   ],
   "common/test-setting-immutable-prototype.js.headers": [
@@ -496446,7 +496621,7 @@
    "testharness"
   ],
   "content-security-policy/generic/eval-typecheck-callout-order.tentative.html": [
-   "7b3c12e396445ff72480a1e9c7cc77550f93f75c",
+   "0be7cf29a284d5f2471c7ada0b5cd643b6f0fb6a",
    "testharness"
   ],
   "content-security-policy/generic/eval-typecheck-callout-order.tentative.html.headers": [
@@ -498750,7 +498925,7 @@
    "testharness"
   ],
   "cookie-store/cookieStoreManager_getSubscriptions_multiple.tentative.https.any.js": [
-   "625f521261507b0c82d5e059f40537f84dfee4c8",
+   "030297e4095efded911308a5de13ae1abad345de",
    "testharness"
   ],
   "cookie-store/cookieStoreManager_getSubscriptions_single.tentative.https.any.js": [
@@ -500998,11 +501173,11 @@
    "testharness"
   ],
   "cookies/samesite/window-open-reload.https.html": [
-   "9c30bd5ca6760c23803fcf951cd772d8a8b39a1d",
+   "ee2091b1373a1da7068722c2557332e3a7f60b05",
    "testharness"
   ],
   "cookies/samesite/window-open.https.html": [
-   "fe2318acc43d857e0a7890d77b95a80f5b060863",
+   "d685eb47fd07872116caa22d2b8ca23774f26a81",
    "testharness"
   ],
   "cookies/secure/set-from-dom.https.sub.html": [
@@ -574569,6 +574744,10 @@
    "b3de59562bc1ff6b78d9c7b29a5836d47bf8a81b",
    "reftest"
   ],
+  "css/css-flexbox/percentage-heights-010.html": [
+   "003cc2487ae56d0172c9253be663b5c3dfdf83ff",
+   "reftest"
+  ],
   "css/css-flexbox/percentage-padding-001.html": [
    "8bba5d60f5cae1b93df70c1973a473f163020a51",
    "testharness"
@@ -627382,7 +627561,7 @@
    "support"
   ],
   "css/cssom-view/MediaQueryList-addListener-handleEvent.html": [
-   "5bdd9dfc9ced8459b459970cf187456c3f82fbe4",
+   "47267d98bbaf66e07ee0e2ef3e37d01231d03f12",
    "testharness"
   ],
   "css/cssom-view/MediaQueryList-addListener-removeListener.html": [
@@ -628138,7 +628317,7 @@
    "testharness"
   ],
   "css/cssom/CSSStyleSheet.html": [
-   "90cfb02751fa540ae29d12357deb41c3671a7567",
+   "d38efc280232c182db8c301714083a0e3d002413",
    "testharness"
   ],
   "css/cssom/HTMLLinkElement-disabled-001.tentative.html": [
@@ -628474,7 +628653,7 @@
    "testharness"
   ],
   "css/cssom/medialist-interfaces-002.html": [
-   "9820015f5e02642ea4c544184811f9f243ee83c5",
+   "210ace1393a12c34323983dddf9b11467cb38d94",
    "testharness"
   ],
   "css/cssom/medialist-interfaces-003.html": [
@@ -642298,7 +642477,7 @@
    "testharness"
   ],
   "custom-elements/historical.html": [
-   "70981ce59c41dd352bccf1b70a1cb7c8cecf30ec",
+   "5a961b13ad7f44f64b3df6dafeeb9321e8bf6762",
    "testharness"
   ],
   "custom-elements/htmlconstructor/newtarget.html": [
@@ -643174,7 +643353,7 @@
    "testharness"
   ],
   "dom/events/EventListener-handleEvent.html": [
-   "1eb80ccb15f0bc6fda7d04d4fc01555ea6b8ab04",
+   "27730b20c584dab38b95baecc5c3b8ae459f491c",
    "testharness"
   ],
   "dom/events/EventListener-incumbent-global-1.sub.html": [
@@ -647298,7 +647477,7 @@
    "testharness"
   ],
   "encoding/textdecoder-fatal.any.js": [
-   "5884f11ec3cf145e2d405e30e3ce346abfc97c1b",
+   "ba8aa5d06c3e2dfea532c70f30bb0841f6966a72",
    "testharness"
   ],
   "encoding/textdecoder-ignorebom.any.js": [
@@ -649514,7 +649693,7 @@
    "testharness"
   ],
   "fetch/api/basic/keepalive.html": [
-   "5316410004a7880ff4d24234d4508680c29a6720",
+   "447ef2ddfecd7a62c4bf9f3d19af4e31e9fe68bc",
    "testharness"
   ],
   "fetch/api/basic/mediasource.window.js": [
@@ -649718,7 +649897,7 @@
    "testharness"
   ],
   "fetch/api/headers/headers-record.html": [
-   "85dfadd269d2c7460865dc5d1b16ae1b9834a5a8",
+   "34acc3b1c557ce7bc1841ad3d785fb1f732f299f",
    "testharness"
   ],
   "fetch/api/headers/headers-structure.html": [
@@ -650158,7 +650337,7 @@
    "support"
   ],
   "fetch/api/resources/keepalive-iframe.html": [
-   "742309ab4d238404b3ad66f8160c24fd5d16ef66",
+   "47de0da7790618224f70171c12dc8fd04436c0e3",
    "support"
   ],
   "fetch/api/resources/method.py": [
@@ -650186,7 +650365,7 @@
    "support"
   ],
   "fetch/api/resources/stash-put.py": [
-   "dd84ff1fc852cfc143231f717366c61b12e3c30c",
+   "36527b98b71785809cd6a490196dd9112fef9181",
    "support"
   ],
   "fetch/api/resources/stash-take.py": [
@@ -650510,7 +650689,7 @@
    "testharness"
   ],
   "fetch/corb/script-resource-with-nonsniffable-types.tentative.sub.html": [
-   "917e54984f460fc1f5a9c13c9ae4520492e17355",
+   "255ff1da267af5a3fead4ad3f94584d70d9bdf4f",
    "testharness"
   ],
   "fetch/corb/style-css-mislabeled-as-html-nosniff.sub.html": [
@@ -652290,7 +652469,7 @@
    "support"
   ],
   "generic-sensor/SensorErrorEvent-constructor.https.html": [
-   "6e2d1684f57af55a6ca02a982d037250ab4c372a",
+   "2d68dec56d9a9d6982e5ba729e3a201625f368df",
    "testharness"
   ],
   "generic-sensor/generic-sensor-feature-policy-test.sub.js": [
@@ -654582,7 +654761,7 @@
    "testharness"
   ],
   "html/browsers/origin/cross-origin-objects/cross-origin-objects.html": [
-   "f16a18d639cc6e528b561d800088fcfebf2c10cf",
+   "2c92d5e51ad8078cec4f6e5e76035a52df93a245",
    "testharness"
   ],
   "html/browsers/origin/cross-origin-objects/frame-with-then.html": [
@@ -655570,7 +655749,7 @@
    "support"
   ],
   "html/cross-origin-embedder-policy/require-corp.https.html": [
-   "49b2eb123b519dc96314b1db31cc4d6797efae92",
+   "8747d29e9343cdfae1d534a39947783ad26ef29c",
    "testharness"
   ],
   "html/cross-origin-embedder-policy/require-corp.https.html.headers": [
@@ -661098,7 +661277,7 @@
    "testharness"
   ],
   "html/infrastructure/common-dom-interfaces/collections/htmlallcollection.html": [
-   "e3e0778c97a2a04ded5a151d31b1dc4f82334187",
+   "095931ad785553a9b64d79d96eacebcb021e3171",
    "testharness"
   ],
   "html/infrastructure/common-dom-interfaces/collections/htmlformcontrolscollection.html": [
@@ -663393,6 +663572,10 @@
    "ef8ac89c4663e970366401bcaa501b774e410c67",
    "testharness"
   ],
+  "html/semantics/document-metadata/the-style-element/style_load_event.html": [
+   "911a088c2ab37e0a457c28aa75b477d1af6561df",
+   "testharness"
+  ],
   "html/semantics/document-metadata/the-style-element/style_media.html": [
    "5bd189a2635dae4b17348023d70e29614eed7e50",
    "testharness"
@@ -664634,7 +664817,7 @@
    "testharness"
   ],
   "html/semantics/embedded-content/media-elements/track/track-element/track-cue-mutable.html": [
-   "63c3018aa9969e819ca8e0109141534467a4bfeb",
+   "cb28f6591ce9614d6a1aa3e0ea7b753d6cb713df",
    "testharness"
   ],
   "html/semantics/embedded-content/media-elements/track/track-element/track-cue-negative-duration.html": [
@@ -674542,7 +674725,7 @@
    "support"
   ],
   "interfaces/IndexedDB.idl": [
-   "33925d614238d6850c196381df0f60ac14bd4e4f",
+   "a66a245466ecb166836df87b50424a5f5c23de35",
    "support"
   ],
   "interfaces/InputDeviceCapabilities.idl": [
@@ -674853,6 +675036,10 @@
    "f7d3f20e72364a1bf7df019e3115c34c10d811ba",
    "support"
   ],
+  "interfaces/native-file-system.idl": [
+   "f4679175c46ec7831f0c6423b0075d95ab99dbe0",
+   "support"
+  ],
   "interfaces/navigation-timing.idl": [
    "57cea306d9e3b50b269587444ecf4c5190e15de4",
    "support"
@@ -675146,7 +675333,7 @@
    "testharness"
   ],
   "intersection-observer/document-scrolling-element-root.html": [
-   "9996299312c996f3705af12e35c6eab088905047",
+   "443ff2ed85f988c66459952ce468bbcf14fdf2e2",
    "testharness"
   ],
   "intersection-observer/edge-inclusive-intersection.html": [
@@ -675382,7 +675569,7 @@
    "support"
   ],
   "js/behaviours/SetPrototypeOf-window.html": [
-   "0a6ec249fa3b8a3df2770e111bbde03ce181c833",
+   "f104ca107c5c5a6e868bdf4153406d98f0b40dc4",
    "testharness"
   ],
   "js/builtins/Array.DefineOwnProperty.html": [
@@ -677654,7 +677841,7 @@
    "testharness"
   ],
   "media-source/mediasource-duration-boundaryconditions.html": [
-   "b95e495cb1dd1a0f119257f35ab514239290e22c",
+   "e5be9f18fc4620250b4cb5ad97b2dce5ae091db1",
    "testharness"
   ],
   "media-source/mediasource-duration.html": [
@@ -678226,7 +678413,7 @@
    "testharness"
   ],
   "mediacapture-record/BlobEvent-constructor.html": [
-   "3bcf4296e68aea1a7b167e570c0dcec148cc95e4",
+   "66dc3404d78020108edc823292bff9b83cda42a6",
    "testharness"
   ],
   "mediacapture-record/META.yml": [
@@ -678462,7 +678649,7 @@
    "testharness"
   ],
   "mediacapture-streams/MediaStreamTrackEvent-constructor.https.html": [
-   "8f5a543d8fbed8b046deab4672729a112842faba",
+   "4946cd71d8125f678af69c87042cc61ddb5b57a5",
    "testharness"
   ],
   "mediacapture-streams/historical.https.html": [
@@ -678498,11 +678685,11 @@
    "testharness"
   ],
   "mediasession/positionstate.html": [
-   "2eab2986d4583c1a289b7876010193c8d3d44b3f",
+   "9033a7be5ce5909e0de9d73e8e6aa02c84387e4d",
    "testharness"
   ],
   "mediasession/setactionhandler.html": [
-   "6e1bb26c67a828ae847734070024b404138e7932",
+   "8f1330f82899e513f1183452490aa0f25b1a6f74",
    "testharness"
   ],
   "mimesniff/META.yml": [
@@ -681177,6 +681364,10 @@
    "6905a68e7901ce26bc1a363062304e1536604400",
    "support"
   ],
+  "native-file-system/idlharness.https.any.js": [
+   "567912ddd7788b871b00a2929f17dc47280dd2d7",
+   "testharness"
+  ],
   "native-file-system/native_FileSystemBaseHandle-postMessage-BroadcastChannel-manual.https.tentative.html": [
    "322b169985bf40e2bac1dba813e840e951f89414",
    "manual"
@@ -689105,7 +689296,7 @@
    "d31ac2dd72abcf51a28ecec850400f5f0c6b9bb5",
    "testharness"
   ],
-  "payment-request/onpaymentmenthodchange-attribute.https.html": [
+  "payment-request/onpaymentmethodchange-attribute.https.html": [
    "f641bec4aa91d8be4f1801869eb699ca4bad03a0",
    "testharness"
   ],
@@ -691005,6 +691196,42 @@
    "f2f7eab4e33858b571344940c67de9b50e18e119",
    "support"
   ],
+  "referrer-policy/4K+1/generic/spec_json.js": [
+   "39cd997338e4c9e235d30097d970daeff5f1f19b",
+   "support"
+  ],
+  "referrer-policy/4K+1/generic/test-case.sub.js": [
+   "b602d65f4141da242b1a9c47b2544cb3e9abc39c",
+   "support"
+  ],
+  "referrer-policy/4K+1/spec.src.json": [
+   "5dc2085c62fa48787d4c16da422e3551eb844630",
+   "support"
+  ],
+  "referrer-policy/4K-1/generic/spec_json.js": [
+   "39cd997338e4c9e235d30097d970daeff5f1f19b",
+   "support"
+  ],
+  "referrer-policy/4K-1/generic/test-case.sub.js": [
+   "5b6aa4216b74a04a193ce7ece447b890d2ec6469",
+   "support"
+  ],
+  "referrer-policy/4K-1/spec.src.json": [
+   "5dc2085c62fa48787d4c16da422e3551eb844630",
+   "support"
+  ],
+  "referrer-policy/4K/generic/spec_json.js": [
+   "39cd997338e4c9e235d30097d970daeff5f1f19b",
+   "support"
+  ],
+  "referrer-policy/4K/generic/test-case.sub.js": [
+   "912c06e10e7f0917c2cf83bb28f2a0975e103c7c",
+   "support"
+  ],
+  "referrer-policy/4K/spec.src.json": [
+   "5dc2085c62fa48787d4c16da422e3551eb844630",
+   "support"
+  ],
   "referrer-policy/META.yml": [
    "8ead043aad0a6aa79dad5c2c9e9b757df5869265",
    "support"
@@ -703210,7 +703437,7 @@
    "testharness"
   ],
   "referrer-policy/generic/test-case.sub.js": [
-   "c8a6b139f33fa044ddb644409b1e4437d3df338c",
+   "a8292e57e1fe32efbed35a184fd7461198643dd1",
    "support"
   ],
   "referrer-policy/generic/unsupported-csp-referrer-directive.html": [
@@ -707474,7 +707701,7 @@
    "support"
   ],
   "service-workers/service-worker/resources/interfaces-worker.sub.js": [
-   "ac79ddc005688affe9acc67b83f43ef304f81c81",
+   "44bd0870b9561eff46eaf1e56aa27912ce0c11a7",
    "support"
   ],
   "service-workers/service-worker/resources/invalid-blobtype-iframe.https.html": [
@@ -720162,7 +720389,7 @@
    "support"
   ],
   "tools/wptrunner/requirements.txt": [
-   "328b43a0737b98503ae0b85dabb35b3a38d958e0",
+   "ccf55d2ca7f15f16d779971ec70c2070dcadf921",
    "support"
   ],
   "tools/wptrunner/requirements_android_webview.txt": [
@@ -720450,7 +720677,7 @@
    "support"
   ],
   "tools/wptrunner/wptrunner/executors/base.py": [
-   "3d8af4de4868e9da86b38d1c9d7b32ed0bfd265b",
+   "603c606e1cde1de879f4fcb2d82f98952de96ce7",
    "support"
   ],
   "tools/wptrunner/wptrunner/executors/executorchrome.py": [
@@ -720570,7 +720797,7 @@
    "support"
   ],
   "tools/wptrunner/wptrunner/manifestexpected.py": [
-   "65b53f0ab97b581b2b71277bd8f260f79a1afb12",
+   "335b0da5c907f649a4bec803ebc25ed7ff54faf8",
    "support"
   ],
   "tools/wptrunner/wptrunner/manifestinclude.py": [
@@ -720586,7 +720813,7 @@
    "support"
   ],
   "tools/wptrunner/wptrunner/process.py": [
-   "26e11ddfc8758e95d7f5048596ab8cae4f4bb546",
+   "8a2b894cb74d4ec091931bf417c92d5bea071cae",
    "support"
   ],
   "tools/wptrunner/wptrunner/products.py": [
@@ -721070,7 +721297,7 @@
    "support"
   ],
   "tools/wptserve/wptserve/handlers.py": [
-   "efc1a16a93225d033574a22f7ba81e7d3d50bfd9",
+   "c18fa2d3792597a4c2a850dda233be56590c67ea",
    "support"
   ],
   "tools/wptserve/wptserve/logger.py": [
@@ -721078,7 +721305,7 @@
    "support"
   ],
   "tools/wptserve/wptserve/pipes.py": [
-   "e5d6e1c96db9c18020ed2b8aee23d41dd503509a",
+   "3500948fc8c296daa3baf6ba0965f8262ddf9fb3",
    "support"
   ],
   "tools/wptserve/wptserve/ranges.py": [
@@ -721246,7 +721473,7 @@
    "testharness"
   ],
   "trusted-types/TrustedTypePolicy-CSP.tentative.html": [
-   "0b57c3a908a9a6218d45c4692ee6fd901e49328b",
+   "8ae162558f41fe0b8015292fe8be84433469311e",
    "testharness"
   ],
   "trusted-types/TrustedTypePolicy-createXXX.tentative.html": [
@@ -721274,7 +721501,7 @@
    "testharness"
   ],
   "trusted-types/TrustedTypePolicyFactory-createPolicy-cspTests.tentative.html": [
-   "0b57c3a908a9a6218d45c4692ee6fd901e49328b",
+   "8ae162558f41fe0b8015292fe8be84433469311e",
    "testharness"
   ],
   "trusted-types/TrustedTypePolicyFactory-createPolicy-nameTests.tentative.html": [
@@ -724846,7 +725073,7 @@
    "testharness"
   ],
   "url/failure.html": [
-   "bebdb3dcc4df6ba11a16a1b2a2b450fb610c0f76",
+   "ac16edf8c743af2650b2b78f570c84f2bc75ecda",
    "testharness"
   ],
   "url/historical.any.js": [
@@ -724878,7 +725105,7 @@
    "support"
   ],
   "url/toascii.window.js": [
-   "b28c664479a26aafddef076ce73ab448418d91fc",
+   "cdc488ec28526f530031b66b63b3c23ff7dad430",
    "testharness"
   ],
   "url/url-constructor.html": [
@@ -726445,6 +726672,10 @@
    "bd053b389c904ed9b2587ad2817650d31fde7504",
    "testharness"
   ],
+  "wasm/jsapi/table/grow-reftypes.tentative.any.js": [
+   "807aea991bbc82eaa4702a12f5b1093baaef6d10",
+   "testharness"
+  ],
   "wasm/jsapi/table/grow.any.js": [
    "558b49d1c7d3bcba9798370792fa4b6f83332105",
    "testharness"
@@ -726754,7 +726985,7 @@
    "testharness"
   ],
   "web-animations/interfaces/Animatable/animate.html": [
-   "95d7db7bb3ba36fc9a0914ebe0d2c8e910e29cf1",
+   "4d17d2dd00ece70673cdd9ca52a77d540c3eac43",
    "testharness"
   ],
   "web-animations/interfaces/Animatable/getAnimations.html": [
@@ -726826,7 +727057,7 @@
    "testharness"
   ],
   "web-animations/interfaces/AnimationEffect/updateTiming.html": [
-   "746f0d74f19272b0cb4a63b27102642b5eaba459",
+   "f4f672ab1aac76905e3258144fbf022201df0f53",
    "testharness"
   ],
   "web-animations/interfaces/AnimationPlaybackEvent/constructor.html": [
@@ -726874,11 +727105,11 @@
    "testharness"
   ],
   "web-animations/interfaces/KeyframeEffect/processing-a-keyframes-argument-002.html": [
-   "8233dc07c5de8d17619489e0d759c75c4d2a059f",
+   "e78e13d69aa5e8004c4ec49de2bc98b6bfb6a54a",
    "testharness"
   ],
   "web-animations/interfaces/KeyframeEffect/setKeyframes.html": [
-   "675a705891fa6c75c233179e59cc73cc516ff48c",
+   "a5c81a29bd9d975c93e652edb614f6dbb1570e3b",
    "testharness"
   ],
   "web-animations/interfaces/KeyframeEffect/style-change-events.html": [
@@ -727210,7 +727441,7 @@
    "support"
   ],
   "web-nfc/NDEFMessage_constructor.https.html": [
-   "4e53828c310976b5b37657f84a89f03c48e7bc59",
+   "5d6b557e3ccf73d078e9dc0eda63ca31a28551b8",
    "testharness"
   ],
   "web-nfc/NDEFReader-document-hidden-manual.https.html": [
@@ -727230,11 +727461,11 @@
    "testharness"
   ],
   "web-nfc/NDEFReadingEvent_constructor.https.html": [
-   "5427b75ae2b6d0fa6c45b24af51b02a8737ffd0b",
+   "122070f50ed7c4fdb15947cbec68e2a62eea9a06",
    "testharness"
   ],
   "web-nfc/NDEFRecord_constructor.https.html": [
-   "a2ea09fa681aff85e0cf69d217a89e9a79a8d96b",
+   "bf4697f8b17ca97de735dc0851a2f48766b1a6b6",
    "testharness"
   ],
   "web-nfc/NDEFWriter-document-hidden-manual.https.html": [
@@ -730094,7 +730325,7 @@
    "testharness"
   ],
   "webmessaging/with-options/null-transfer.html": [
-   "72bebd1e38e8c5538ebaf24fe608048bed61d18d",
+   "2ea09eb7ab4ada86bd4624e222fbdebc026d95e8",
    "testharness"
   ],
   "webmessaging/with-options/one-arg.html": [
@@ -730190,7 +730421,7 @@
    "testharness"
   ],
   "webmessaging/with-ports/023.html": [
-   "da6a5c49a448c2ce502fe09a0693ce15abb6e00d",
+   "e2569a8463f51f0691f572de7024cd93936adb20",
    "testharness"
   ],
   "webmessaging/with-ports/024.html": [
@@ -730353,6 +730584,10 @@
    "4ceee0664cbfb800ac8b410c295dde4c7009b024",
    "support"
   ],
+  "webrtc-extensions/RTCRtpParameters-maxFramerate.html": [
+   "7067fbc79980743867c0c497c359e96c736ed400",
+   "testharness"
+  ],
   "webrtc-extensions/RTCRtpReceiver-playoutDelayHint.html": [
    "d8e47bda22174c63094c0918ccabed63513ea9fa",
    "testharness"
@@ -730362,7 +730597,7 @@
    "support"
   ],
   "webrtc-identity/RTCPeerConnection-constructor.html": [
-   "8498e6b35c9ff820c86773dd874930c5b012229e",
+   "e7b7016338d8b8865b95098a0ec6f7eb2b65c4fb",
    "testharness"
   ],
   "webrtc-identity/RTCPeerConnection-getIdentityAssertion.sub.https.html": [
@@ -730574,7 +730809,7 @@
    "testharness"
   ],
   "webrtc/RTCPeerConnection-createDataChannel.html": [
-   "943e5728775494b8c5be4c521ce9671cd4e1bc4e",
+   "350f71567820f80506fdc6d86452784521f0ff40",
    "testharness"
   ],
   "webrtc/RTCPeerConnection-createOffer.html": [
@@ -730738,7 +730973,7 @@
    "testharness"
   ],
   "webrtc/RTCRtpParameters-encodings.html": [
-   "c9e14cb374b232b8f9df0472f082b16cc02f9f28",
+   "f71964429ae6bdb055157ead1af990e0e6716c6d",
    "testharness"
   ],
   "webrtc/RTCRtpParameters-headerExtensions.html": [
@@ -730746,7 +730981,7 @@
    "testharness"
   ],
   "webrtc/RTCRtpParameters-helper.js": [
-   "d70694930086590ab3616c1cde0fec419c1b63da",
+   "d61d8e14932963e9f17c47b99f2998d7ef0e9ff4",
    "support"
   ],
   "webrtc/RTCRtpParameters-rtcp.html": [
@@ -732046,11 +732281,11 @@
    "support"
   ],
   "webstorage/event_constructor.html": [
-   "fe7fca77a93c7adec48dc31e7926331e427b969b",
+   "e0bb3f374f4326267e509b4605a7f573a13a627b",
    "testharness"
   ],
   "webstorage/event_initstorageevent.html": [
-   "2fe893143614ca6d44becd027f6befba82e18ad1",
+   "b06a01617a832d51941bc5b351bfc1a6a9f07a59",
    "testharness"
   ],
   "webstorage/event_local_key.html": [
@@ -732478,7 +732713,7 @@
    "support"
   ],
   "webvtt/api/VTTCue/constructor-exceptions.html": [
-   "4d051fb3e981811961c3491297955542acbe445d",
+   "843cab098456c963912cbe255b23b2f9bef14f67",
    "testharness"
   ],
   "webvtt/api/VTTCue/constructor.html": [
@@ -737110,7 +737345,7 @@
    "support"
   ],
   "workers/modules/dedicated-worker-import-blob-url.any.js": [
-   "f51a821d1813df81187e8c78d6251f9f29cf45eb",
+   "e5d79add73661e6a814fe77ccd783f651c56319c",
    "testharness"
   ],
   "workers/modules/dedicated-worker-import-csp.html": [
@@ -737122,11 +737357,11 @@
    "testharness"
   ],
   "workers/modules/dedicated-worker-import-failure.html": [
-   "439bea888b2bac65f5de50d47c12639fd49168a4",
+   "5e8b152195a354022943ae9404bb4473d3cd0c0d",
    "testharness"
   ],
   "workers/modules/dedicated-worker-import-meta.html": [
-   "9292b0f6d8ef8f543cbdc060b64cf2826bac1ac4",
+   "4ed56e279f7d558ca5d75c6cbe969ba41b2d52dd",
    "testharness"
   ],
   "workers/modules/dedicated-worker-import-referrer.html": [
@@ -737134,7 +737369,7 @@
    "testharness"
   ],
   "workers/modules/dedicated-worker-import.any.js": [
-   "308c5e74c157da005257fd03fa9bc714c6d0eee7",
+   "d5bb6cccbe21a3050f57dc8b3378e3e04fb7b03c",
    "testharness"
   ],
   "workers/modules/dedicated-worker-options-credentials.html": [
@@ -737146,7 +737381,7 @@
    "support"
   ],
   "workers/modules/dedicated-worker-options-type.html": [
-   "b7c96b152950dda87ff0a34192008a6e30ec7471",
+   "74523f4478b4209d4de060e98553946896fdecb7",
    "testharness"
   ],
   "workers/modules/resources/credentials.py": [
@@ -737282,7 +737517,7 @@
    "support"
   ],
   "workers/modules/shared-worker-import-blob-url.any.js": [
-   "d9e9e34c394bc171cd497c8527b4806dfc32c595",
+   "f56c1a5525f8c46e5d06f6549b3f355c4ccb4a0a",
    "testharness"
   ],
   "workers/modules/shared-worker-import-failure.html": [
@@ -737290,7 +737525,7 @@
    "testharness"
   ],
   "workers/modules/shared-worker-import.any.js": [
-   "450d4ad422b8da33d515da9b41557f488aff8bff",
+   "15dfdde067a347b024c078578f24a5c63ae53fdd",
    "testharness"
   ],
   "workers/modules/shared-worker-options-type.html": [
diff --git a/tests/wpt/metadata/css/css-flexbox/percentage-heights-010.html.ini b/tests/wpt/metadata/css/css-flexbox/percentage-heights-010.html.ini
new file mode 100644
index 00000000000..e8a75b458af
--- /dev/null
+++ b/tests/wpt/metadata/css/css-flexbox/percentage-heights-010.html.ini
@@ -0,0 +1,2 @@
+[percentage-heights-010.html]
+  expected: FAIL
diff --git a/tests/wpt/metadata/css/cssom-view/CaretPosition-001.html.ini b/tests/wpt/metadata/css/cssom-view/CaretPosition-001.html.ini
deleted file mode 100644
index 4c79907309b..00000000000
--- a/tests/wpt/metadata/css/cssom-view/CaretPosition-001.html.ini
+++ /dev/null
@@ -1,4 +0,0 @@
-[CaretPosition-001.html]
-  [Element at (400, 100)]
-    expected: FAIL
-
diff --git a/tests/wpt/metadata/css/cssom-view/MediaQueryList-addListener-handleEvent.html.ini b/tests/wpt/metadata/css/cssom-view/MediaQueryList-addListener-handleEvent.html.ini
index 9997350495a..a6c39d50087 100644
--- a/tests/wpt/metadata/css/cssom-view/MediaQueryList-addListener-handleEvent.html.ini
+++ b/tests/wpt/metadata/css/cssom-view/MediaQueryList-addListener-handleEvent.html.ini
@@ -1,11 +1,10 @@
 [MediaQueryList-addListener-handleEvent.html]
-  expected: TIMEOUT
   [throws if handleEvent is falsy and not callable]
-    expected: NOTRUN
+    expected: FAIL
 
   [rethrows errors when getting handleEvent]
-    expected: TIMEOUT
+    expected: FAIL
 
   [throws if handleEvent is thruthy and not callable]
-    expected: NOTRUN
+    expected: FAIL
 
diff --git a/tests/wpt/metadata/css/cssom-view/MediaQueryList-addListener-removeListener.html.ini b/tests/wpt/metadata/css/cssom-view/MediaQueryList-addListener-removeListener.html.ini
index c884dc82eab..628b1fab770 100644
--- a/tests/wpt/metadata/css/cssom-view/MediaQueryList-addListener-removeListener.html.ini
+++ b/tests/wpt/metadata/css/cssom-view/MediaQueryList-addListener-removeListener.html.ini
@@ -2,6 +2,3 @@
   [listeners are called when <iframe> is resized]
     expected: FAIL
 
-  [listeners are called correct number of times]
-    expected: FAIL
-
diff --git a/tests/wpt/metadata/fetch/api/basic/keepalive.html.ini b/tests/wpt/metadata/fetch/api/basic/keepalive.html.ini
new file mode 100644
index 00000000000..09078126c43
--- /dev/null
+++ b/tests/wpt/metadata/fetch/api/basic/keepalive.html.ini
@@ -0,0 +1,4 @@
+[keepalive.html]
+  [cross-origin redirect with preflight]
+    expected: FAIL
+
diff --git a/tests/wpt/metadata/fetch/content-type/response.window.js.ini b/tests/wpt/metadata/fetch/content-type/response.window.js.ini
index ad82111842c..f10cc491003 100644
--- a/tests/wpt/metadata/fetch/content-type/response.window.js.ini
+++ b/tests/wpt/metadata/fetch/content-type/response.window.js.ini
@@ -312,24 +312,12 @@
   [fetch(): separate response Content-Type: text/plain ]
     expected: NOTRUN
 
-  [<iframe>: combined response Content-Type: text/html */*]
-    expected: FAIL
-
-  [<iframe>: separate response Content-Type: text/html */*;charset=gbk]
-    expected: FAIL
-
-  [<iframe>: combined response Content-Type: text/html;" text/plain]
-    expected: FAIL
-
-  [<iframe>: combined response Content-Type: */* text/html]
-    expected: FAIL
-
   [<iframe>: combined response Content-Type: text/html */*;charset=gbk]
     expected: FAIL
 
-  [<iframe>: combined response Content-Type: text/html;" \\" text/plain]
+  [<iframe>: separate response Content-Type: text/html;" \\" text/plain]
     expected: FAIL
 
-  [<iframe>: separate response Content-Type: text/plain */*;charset=gbk]
+  [<iframe>: combined response Content-Type: text/html;x=" text/plain]
     expected: FAIL
 
diff --git a/tests/wpt/metadata/fetch/nosniff/parsing-nosniff.window.js.ini b/tests/wpt/metadata/fetch/nosniff/parsing-nosniff.window.js.ini
index 536384f36e1..cddaebcd819 100644
--- a/tests/wpt/metadata/fetch/nosniff/parsing-nosniff.window.js.ini
+++ b/tests/wpt/metadata/fetch/nosniff/parsing-nosniff.window.js.ini
@@ -11,6 +11,9 @@
   [X-Content-Type-Options%3A%20nosniff%0C]
     expected: FAIL
 
-  [X-Content-Type-Options%3A%20%2Cnosniff]
+  [X-Content-Type-Options%3A%20%40%23%24%23%25%25%26%5E%26%5E*()()11!%2Cnosniff]
+    expected: FAIL
+
+  [Content-Type-Options%3A%20nosniff]
     expected: FAIL
 
diff --git a/tests/wpt/metadata/html/browsers/history/the-history-interface/traverse_the_history_1.html.ini b/tests/wpt/metadata/html/browsers/history/the-history-interface/traverse_the_history_1.html.ini
deleted file mode 100644
index 87b07c3e670..00000000000
--- a/tests/wpt/metadata/html/browsers/history/the-history-interface/traverse_the_history_1.html.ini
+++ /dev/null
@@ -1,4 +0,0 @@
-[traverse_the_history_1.html]
-  [Multiple history traversals from the same task]
-    expected: FAIL
-
diff --git a/tests/wpt/metadata/html/browsers/history/the-history-interface/traverse_the_history_4.html.ini b/tests/wpt/metadata/html/browsers/history/the-history-interface/traverse_the_history_5.html.ini
similarity index 71%
rename from tests/wpt/metadata/html/browsers/history/the-history-interface/traverse_the_history_4.html.ini
rename to tests/wpt/metadata/html/browsers/history/the-history-interface/traverse_the_history_5.html.ini
index 385376c7321..dc2e45516de 100644
--- a/tests/wpt/metadata/html/browsers/history/the-history-interface/traverse_the_history_4.html.ini
+++ b/tests/wpt/metadata/html/browsers/history/the-history-interface/traverse_the_history_5.html.ini
@@ -1,4 +1,4 @@
-[traverse_the_history_4.html]
+[traverse_the_history_5.html]
   [Multiple history traversals, last would be aborted]
     expected: FAIL
 
diff --git a/tests/wpt/metadata/html/interaction/focus/the-autofocus-attribute/skip-document-with-fragment.html.ini b/tests/wpt/metadata/html/interaction/focus/the-autofocus-attribute/skip-document-with-fragment.html.ini
index 6852d7663de..c12c0f8ae48 100644
--- a/tests/wpt/metadata/html/interaction/focus/the-autofocus-attribute/skip-document-with-fragment.html.ini
+++ b/tests/wpt/metadata/html/interaction/focus/the-autofocus-attribute/skip-document-with-fragment.html.ini
@@ -1,8 +1,4 @@
 [skip-document-with-fragment.html]
-  expected: TIMEOUT
   [Autofocus elements in iframed documents with URL fragments should be skipped.]
     expected: FAIL
 
-  [Autofocus elements in top-level browsing context's documents with URI fragments should be skipped.]
-    expected: TIMEOUT
-
diff --git a/tests/wpt/metadata/html/semantics/document-metadata/the-style-element/style_load_event.html.ini b/tests/wpt/metadata/html/semantics/document-metadata/the-style-element/style_load_event.html.ini
new file mode 100644
index 00000000000..3e03bdfdf77
--- /dev/null
+++ b/tests/wpt/metadata/html/semantics/document-metadata/the-style-element/style_load_event.html.ini
@@ -0,0 +1,4 @@
+[style_load_event.html]
+  [style load event should fire when textContent changed]
+    expected: FAIL
+
diff --git a/tests/wpt/metadata/html/semantics/scripting-1/the-script-element/script-onerror-insertion-point-2.html.ini b/tests/wpt/metadata/html/semantics/scripting-1/the-script-element/script-onerror-insertion-point-2.html.ini
deleted file mode 100644
index 178680e5d14..00000000000
--- a/tests/wpt/metadata/html/semantics/scripting-1/the-script-element/script-onerror-insertion-point-2.html.ini
+++ /dev/null
@@ -1,2 +0,0 @@
-[script-onerror-insertion-point-2.html]
-  expected: TIMEOUT
diff --git a/tests/wpt/metadata/html/webappapis/dynamic-markup-insertion/opening-the-input-stream/ignore-opens-during-unload.window.js.ini b/tests/wpt/metadata/html/webappapis/dynamic-markup-insertion/opening-the-input-stream/ignore-opens-during-unload.window.js.ini
index 69bd952d756..910c88d3e81 100644
--- a/tests/wpt/metadata/html/webappapis/dynamic-markup-insertion/opening-the-input-stream/ignore-opens-during-unload.window.js.ini
+++ b/tests/wpt/metadata/html/webappapis/dynamic-markup-insertion/opening-the-input-stream/ignore-opens-during-unload.window.js.ini
@@ -1,5 +1,5 @@
 [ignore-opens-during-unload.window.html]
-  expected: TIMEOUT
+  expected: CRASH
   [ignore-opens-during-unload]
     expected: FAIL
 
diff --git a/tests/wpt/metadata/wasm/jsapi/table/grow-reftypes.tentative.any.js.ini b/tests/wpt/metadata/wasm/jsapi/table/grow-reftypes.tentative.any.js.ini
new file mode 100644
index 00000000000..4cbd979537d
--- /dev/null
+++ b/tests/wpt/metadata/wasm/jsapi/table/grow-reftypes.tentative.any.js.ini
@@ -0,0 +1,7 @@
+[grow-reftypes.tentative.any.html]
+  [Grow with exported-function argument]
+    expected: FAIL
+
+
+[grow-reftypes.tentative.any.worker.html]
+  expected: ERROR
diff --git a/tests/wpt/web-platform-tests/2dcontext/imagebitmap/createImageBitmap-in-worker-transfer.html b/tests/wpt/web-platform-tests/2dcontext/imagebitmap/createImageBitmap-in-worker-transfer.html
new file mode 100644
index 00000000000..727a8a4978d
--- /dev/null
+++ b/tests/wpt/web-platform-tests/2dcontext/imagebitmap/createImageBitmap-in-worker-transfer.html
@@ -0,0 +1,20 @@
+<!DOCTYPE html>
+<meta charset=utf-8>
+<title>createImageBitmap in worker and transfer</title>
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<div id=log></div>
+<script>
+promise_test(function(t) {
+    return new Promise(function(resolve, reject) {
+        var worker = new Worker("createImageBitmap-worker.js");
+        worker.addEventListener("message", function(evt) {
+            var bitmap = evt.data;
+            assert_equals(bitmap.width, 20);
+            assert_equals(bitmap.height, 20);
+            resolve();
+        });
+        worker.postMessage('test');
+    });
+}, 'Transfer ImageBitmap created in worker');
+</script>
diff --git a/tests/wpt/web-platform-tests/2dcontext/imagebitmap/createImageBitmap-worker.js b/tests/wpt/web-platform-tests/2dcontext/imagebitmap/createImageBitmap-worker.js
new file mode 100644
index 00000000000..67a0904e479
--- /dev/null
+++ b/tests/wpt/web-platform-tests/2dcontext/imagebitmap/createImageBitmap-worker.js
@@ -0,0 +1,17 @@
+function makeBlob() {
+    return new Promise(function(resolve, reject) {
+        var xhr = new XMLHttpRequest();
+        xhr.open("GET", '/images/pattern.png');
+        xhr.responseType = 'blob';
+        xhr.send();
+        xhr.onload = function() {
+            resolve(xhr.response);
+        };
+    });
+}
+
+addEventListener("message", () => {
+    makeBlob().then(createImageBitmap).then(bitmap => {
+        postMessage(bitmap, [bitmap]);
+    });
+});
diff --git a/tests/wpt/web-platform-tests/IndexedDB/idb-binary-key-detached.htm b/tests/wpt/web-platform-tests/IndexedDB/idb-binary-key-detached.htm
index 26afcfb1cd0..5a2e1f79f42 100644
--- a/tests/wpt/web-platform-tests/IndexedDB/idb-binary-key-detached.htm
+++ b/tests/wpt/web-platform-tests/IndexedDB/idb-binary-key-detached.htm
@@ -23,7 +23,7 @@ indexeddb_test(
     worker.postMessage('', [buffer]);
     assert_equals(array.byteLength, 0);
 
-    assert_throws(new TypeError, () => { store.put('', buffer); });
+    assert_throws_js(TypeError, () => { store.put('', buffer); });
     t.done();
   },
   'Detached ArrayBuffer'
@@ -43,7 +43,7 @@ indexeddb_test(
     worker.postMessage('', [array.buffer]);
     assert_equals(array.length, 0);
 
-    assert_throws(new TypeError, () => { store.put('', array); });
+    assert_throws_js(TypeError, () => { store.put('', array); });
     t.done();
   },
   'Detached TypedArray'
diff --git a/tests/wpt/web-platform-tests/IndexedDB/idbcursor-advance-exception-order.html b/tests/wpt/web-platform-tests/IndexedDB/idbcursor-advance-exception-order.html
index 13f7fdae5a5..1e05c9074d6 100644
--- a/tests/wpt/web-platform-tests/IndexedDB/idbcursor-advance-exception-order.html
+++ b/tests/wpt/web-platform-tests/IndexedDB/idbcursor-advance-exception-order.html
@@ -23,7 +23,7 @@ indexeddb_test(
       const cursor = r.result;
 
       setTimeout(t.step_func(() => {
-        assert_throws(new TypeError, () => { cursor.advance(0); },
+        assert_throws_js(TypeError, () => { cursor.advance(0); },
                       '"zero" check (TypeError) should precede ' +
                       '"not active" check (TransactionInactiveError)');
         t.done();
diff --git a/tests/wpt/web-platform-tests/IndexedDB/idbkeyrange-includes.htm b/tests/wpt/web-platform-tests/IndexedDB/idbkeyrange-includes.htm
index aea588051ae..9a408e888a4 100644
--- a/tests/wpt/web-platform-tests/IndexedDB/idbkeyrange-includes.htm
+++ b/tests/wpt/web-platform-tests/IndexedDB/idbkeyrange-includes.htm
@@ -8,7 +8,7 @@
 
 test(function() {
   var range = IDBKeyRange.bound(12, 34);
-  assert_throws(new TypeError, function() { range.includes(); },
+  assert_throws_js(TypeError, function() { range.includes(); },
       'throws if key is not specified');
 
   assert_throws('DataError', function() { range.includes(undefined); },
diff --git a/tests/wpt/web-platform-tests/bluetooth/idl/idl-BluetoothUUID.html b/tests/wpt/web-platform-tests/bluetooth/idl/idl-BluetoothUUID.html
index 2adf35a419f..14463127e06 100644
--- a/tests/wpt/web-platform-tests/bluetooth/idl/idl-BluetoothUUID.html
+++ b/tests/wpt/web-platform-tests/bluetooth/idl/idl-BluetoothUUID.html
@@ -142,16 +142,16 @@ test(() => {
   let func = () => {};
 
   // cannonicalUUID
-  assert_throws(new TypeError, () => BluetoothUUID.canonicalUUID(object));
+  assert_throws_js(TypeError, () => BluetoothUUID.canonicalUUID(object));
   // [] converts to '', which converts to 0 before the range check.
   assert_equals(BluetoothUUID.canonicalUUID(array), base_uuid);
-  assert_throws(new TypeError, () => BluetoothUUID.canonicalUUID(func));
-  assert_throws(new TypeError, () => BluetoothUUID.canonicalUUID(undefined));
+  assert_throws_js(TypeError, () => BluetoothUUID.canonicalUUID(func));
+  assert_throws_js(TypeError, () => BluetoothUUID.canonicalUUID(undefined));
   assert_equals(BluetoothUUID.canonicalUUID(null), base_uuid);
   assert_equals(BluetoothUUID.canonicalUUID(false), base_uuid);
   assert_equals(
       BluetoothUUID.canonicalUUID(true), BluetoothUUID.canonicalUUID(1));
-  assert_throws(new TypeError, () => BluetoothUUID.canonicalUUID(NaN));
+  assert_throws_js(TypeError, () => BluetoothUUID.canonicalUUID(NaN));
 
   // getService
   assert_throws(TypeError(), () => BluetoothUUID.getService(object));
diff --git a/tests/wpt/web-platform-tests/common/security-features/README.md b/tests/wpt/web-platform-tests/common/security-features/README.md
index 2509d661b4a..46cabd2bb3c 100644
--- a/tests/wpt/web-platform-tests/common/security-features/README.md
+++ b/tests/wpt/web-platform-tests/common/security-features/README.md
@@ -81,6 +81,41 @@ The generator script has two targets: ```release``` and ```debug```.
 Note that **release** is the default target when invoking ```generate.py```.
 
 
+## Sub projects
+
+Projects can be nested, for example to reuse a single `spec.src.json` across similar but slightly different sets of generated tests.
+The directory structure would look like:
+
+```
+project-directory/ (e.g. referrer-policy/)
+├── spec.src.json - Parent project's spec JSON
+├── generic/
+│   └── test-case.sub.js - Parent project's test helper
+├── gen/ - parent project's generated tests
+└── sub-project-directory/ (e.g. 4K)
+    ├── spec.src.json - Child project's spec JSON
+    ├── generic/
+    │   └── test-case.sub.js - Child project's test helper
+    └── gen/ - child project's generated tests
+```
+
+`generate.py --spec project-directory/sub-project-directory` generates test files under `project-directory/sub-project-directory/gen`, based on `project-directory/spec.src.json` and `project-directory/sub-project-directory/spec.src.json`.
+
+- The child project's `spec.src.json` is merged into parent project's `spec.src.json`.
+    - Two spec JSON objects are merged recursively.
+    - If a same key exists in both objects, the child's value overwrites the parent's value.
+        - If both (child's and parent's) values are arrays, then the child's value is concatenated to the parent's value.
+    - For debugging, `generate.py` dumps the merged spec JSON object as `generic/debug-output.spec.src.json`.
+- The child project's generated tests include both of the parent and child project's `test-case.sub.js`:
+  ```html
+  <script src="project-directory/test-case.sub.js"></script>
+  <script src="project-directory/sub-project-directory/test-case.sub.js"></script>
+  <script>
+    TestCase(...);
+  </script>
+  ```
+
+
 ## Updating the tests
 
 The main test logic lives in ```project-directory/generic/test-case.sub.js``` with helper functions defined in ```/common/security-features/resources/common.js``` so you should probably start there.
diff --git a/tests/wpt/web-platform-tests/common/security-features/tools/format_spec_src_json.py b/tests/wpt/web-platform-tests/common/security-features/tools/format_spec_src_json.py
index b4549bb710c..d1bf5817ad2 100644
--- a/tests/wpt/web-platform-tests/common/security-features/tools/format_spec_src_json.py
+++ b/tests/wpt/web-platform-tests/common/security-features/tools/format_spec_src_json.py
@@ -7,7 +7,9 @@ def main():
     '''Formats spec.src.json.'''
     script_directory = os.path.dirname(os.path.abspath(__file__))
     for dir in [
-            'mixed-content', 'referrer-policy', 'upgrade-insecure-requests'
+            'mixed-content', 'referrer-policy', 'referrer-policy/4K-1',
+            'referrer-policy/4K', 'referrer-policy/4K+1',
+            'upgrade-insecure-requests'
     ]:
         filename = os.path.join(script_directory, '..', '..', '..', dir,
                                 'spec.src.json')
diff --git a/tests/wpt/web-platform-tests/common/security-features/tools/generate.py b/tests/wpt/web-platform-tests/common/security-features/tools/generate.py
index ba997067b3f..3345d652069 100755
--- a/tests/wpt/web-platform-tests/common/security-features/tools/generate.py
+++ b/tests/wpt/web-platform-tests/common/security-features/tools/generate.py
@@ -130,8 +130,8 @@ def handle_deliveries(policy_deliveries):
     return {"meta": meta, "headers": headers}
 
 
-def generate_selection(spec_directory, spec_json, selection, spec,
-                       test_html_template_basename):
+def generate_selection(spec_directory, test_helper_filenames, spec_json,
+                       selection, spec, test_html_template_basename):
     test_filename = get_test_filename(spec_directory, spec_json, selection)
 
     target_policy_delivery = util.PolicyDelivery(selection['delivery_type'],
@@ -184,9 +184,10 @@ def generate_selection(spec_directory, spec_json, selection, spec,
 
     test_directory = os.path.dirname(test_filename)
 
-    selection['helper_js'] = os.path.relpath(
-        os.path.join(spec_directory, 'generic', 'test-case.sub.js'),
-        test_directory)
+    selection['helper_js'] = ""
+    for test_helper_filename in test_helper_filenames:
+        selection['helper_js'] += '    <script src="%s"></script>\n' % (
+            os.path.relpath(test_helper_filename, test_directory))
     selection['sanity_checker_js'] = os.path.relpath(
         os.path.join(spec_directory, 'generic', 'sanity-checker.js'),
         test_directory)
@@ -237,17 +238,20 @@ def generate_selection(spec_directory, spec_json, selection, spec,
     util.write_file(test_filename, test_html_template % selection)
 
 
-def generate_test_source_files(spec_directory, spec_json, target):
+def generate_test_source_files(spec_directory, test_helper_filenames,
+                               spec_json, target):
     test_expansion_schema = spec_json['test_expansion_schema']
     specification = spec_json['specification']
 
     spec_json_js_template = util.get_template('spec_json.js.template')
-    generated_spec_json_filename = os.path.join(spec_directory, "generic",
-                                                "spec_json.js")
     util.write_file(
-        generated_spec_json_filename,
+        os.path.join(spec_directory, "generic", "spec_json.js"),
         spec_json_js_template % {'spec_json': json.dumps(spec_json)})
 
+    util.write_file(
+        os.path.join(spec_directory, "generic", "debug-output.spec.src.json"),
+        json.dumps(spec_json, indent=2, separators=(',', ': ')))
+
     # Choose a debug/release template depending on the target.
     html_template = "test.%s.html.template" % target
 
@@ -290,12 +294,26 @@ def generate_test_source_files(spec_directory, spec_json, target):
                 print('Excluding selection:', selection_path)
                 continue
             try:
-                generate_selection(spec_directory, spec_json, selection, spec,
-                                   html_template)
+                generate_selection(spec_directory, test_helper_filenames,
+                                   spec_json, selection, spec, html_template)
             except util.ShouldSkip:
                 continue
 
 
+def merge_json(base, child):
+    for key in child:
+        if key not in base:
+            base[key] = child[key]
+            continue
+        # `base[key]` and `child[key]` both exists.
+        if isinstance(base[key], list) and isinstance(child[key], list):
+            base[key].extend(child[key])
+        elif isinstance(base[key], dict) and isinstance(child[key], dict):
+            merge_json(base[key], child[key])
+        else:
+            base[key] = child[key]
+
+
 def main():
     parser = argparse.ArgumentParser(
         description='Test suite generator utility')
@@ -317,11 +335,38 @@ def main():
 
     spec_directory = os.path.abspath(args.spec)
 
-    spec_filename = os.path.join(spec_directory, "spec.src.json")
-    spec_json = util.load_spec_json(spec_filename)
-    spec_validator.assert_valid_spec_json(spec_json)
+    # Read `spec.src.json` files, starting from `spec_directory`, and
+    # continuing to parent directories as long as `spec.src.json` exists.
+    spec_filenames = []
+    test_helper_filenames = []
+    spec_src_directory = spec_directory
+    while len(spec_src_directory) >= len(util.test_root_directory):
+        spec_filename = os.path.join(spec_src_directory, "spec.src.json")
+        if not os.path.exists(spec_filename):
+            break
+        spec_filenames.append(spec_filename)
+        test_filename = os.path.join(spec_src_directory, 'generic',
+                                     'test-case.sub.js')
+        assert (os.path.exists(test_filename))
+        test_helper_filenames.append(test_filename)
+        spec_src_directory = os.path.abspath(
+            os.path.join(spec_src_directory, ".."))
 
-    generate_test_source_files(spec_directory, spec_json, args.target)
+    spec_filenames = list(reversed(spec_filenames))
+    test_helper_filenames = list(reversed(test_helper_filenames))
+
+    if len(spec_filenames) == 0:
+        print('Error: No spec.src.json is found at %s.' % spec_directory)
+        return
+
+    spec_json = util.load_spec_json(spec_filenames[0])
+    for spec_filename in spec_filenames[1:]:
+        child_spec_json = util.load_spec_json(spec_filename)
+        merge_json(spec_json, child_spec_json)
+
+    spec_validator.assert_valid_spec_json(spec_json)
+    generate_test_source_files(spec_directory, test_helper_filenames,
+                               spec_json, args.target)
 
 
 if __name__ == '__main__':
diff --git a/tests/wpt/web-platform-tests/common/security-features/tools/template/test.debug.html.template b/tests/wpt/web-platform-tests/common/security-features/tools/template/test.debug.html.template
index b4b0fec733e..f09395cff49 100644
--- a/tests/wpt/web-platform-tests/common/security-features/tools/template/test.debug.html.template
+++ b/tests/wpt/web-platform-tests/common/security-features/tools/template/test.debug.html.template
@@ -15,8 +15,7 @@
     <script src="%(spec_json_js)s"></script>
     <!-- Internal checking of the tests -->
     <script src="%(sanity_checker_js)s"></script>
-    <script src="%(helper_js)s"></script>
-  </head>
+%(helper_js)s  </head>
   <body>
     <script>
       TestCase(
diff --git a/tests/wpt/web-platform-tests/common/security-features/tools/template/test.release.html.template b/tests/wpt/web-platform-tests/common/security-features/tools/template/test.release.html.template
index d93506e231a..6bf79f77df1 100644
--- a/tests/wpt/web-platform-tests/common/security-features/tools/template/test.release.html.template
+++ b/tests/wpt/web-platform-tests/common/security-features/tools/template/test.release.html.template
@@ -11,8 +11,7 @@
     <script src="/resources/testharness.js"></script>
     <script src="/resources/testharnessreport.js"></script>
     <script src="/common/security-features/resources/common.sub.js"></script>
-    <script src="%(helper_js)s"></script>
-  </head>
+%(helper_js)s  </head>
   <body>
     <script>
       TestCase(
diff --git a/tests/wpt/web-platform-tests/common/test-setting-immutable-prototype.js b/tests/wpt/web-platform-tests/common/test-setting-immutable-prototype.js
index 92e61c07424..de619b1d766 100644
--- a/tests/wpt/web-platform-tests/common/test-setting-immutable-prototype.js
+++ b/tests/wpt/web-platform-tests/common/test-setting-immutable-prototype.js
@@ -1,7 +1,7 @@
 self.testSettingImmutablePrototypeToNewValueOnly =
   (prefix, target, newValue, newValueString, { isSameOriginDomain }) => {
   test(() => {
-    assert_throws(new TypeError, () => {
+    assert_throws_js(TypeError, () => {
       Object.setPrototypeOf(target, newValue);
     });
   }, `${prefix}: setting the prototype to ${newValueString} via Object.setPrototypeOf should throw a TypeError`);
diff --git a/tests/wpt/web-platform-tests/content-security-policy/generic/eval-typecheck-callout-order.tentative.html b/tests/wpt/web-platform-tests/content-security-policy/generic/eval-typecheck-callout-order.tentative.html
index 7b3c12e3964..0be7cf29a28 100644
--- a/tests/wpt/web-platform-tests/content-security-policy/generic/eval-typecheck-callout-order.tentative.html
+++ b/tests/wpt/web-platform-tests/content-security-policy/generic/eval-typecheck-callout-order.tentative.html
@@ -10,7 +10,7 @@
 
     <script nonce='abc'>
     test(function() {
-      assert_throws(new EvalError, function() {
+      assert_throws_js(EvalError, function() {
         eval("0");
       }, "eval of a string should reach host callout");
     }, "eval of a string should be checked by CSP");
diff --git a/tests/wpt/web-platform-tests/cookie-store/cookieStoreManager_getSubscriptions_multiple.tentative.https.any.js b/tests/wpt/web-platform-tests/cookie-store/cookieStoreManager_getSubscriptions_multiple.tentative.https.any.js
index 625f5212615..030297e4095 100644
--- a/tests/wpt/web-platform-tests/cookie-store/cookieStoreManager_getSubscriptions_multiple.tentative.https.any.js
+++ b/tests/wpt/web-platform-tests/cookie-store/cookieStoreManager_getSubscriptions_multiple.tentative.https.any.js
@@ -43,7 +43,13 @@ promise_test(async testCase => {
       { name: 'cookie-name1', matchType: 'equals', url: `${scope}/path1` },
     ];
     await registration.cookies.subscribe(subscriptions);
-    testCase.add_cleanup(() => registration.cookies.unsubscribe(subscriptions));
+    testCase.add_cleanup(() => {
+      // For non-ServiceWorker environments, registration.unregister() cleans up
+      // cookie subscriptions.
+      if (self.GLOBAL.isWorker()) {
+        return registration.cookies.unsubscribe(subscriptions);
+      }
+    });
   }
   {
     const subscriptions = [
@@ -51,7 +57,13 @@ promise_test(async testCase => {
       { name: 'cookie-prefix', matchType: 'starts-with' },
     ];
     await registration.cookies.subscribe(subscriptions);
-    testCase.add_cleanup(() => registration.cookies.unsubscribe(subscriptions));
+    testCase.add_cleanup(() => {
+      // For non-ServiceWorker environments, registration.unregister() cleans up
+      // cookie subscriptions.
+      if (self.GLOBAL.isWorker()) {
+        return registration.cookies.unsubscribe(subscriptions);
+      }
+    });
   }
 
   const subscriptions = await registration.cookies.getSubscriptions();
diff --git a/tests/wpt/web-platform-tests/cookies/samesite/window-open-reload.https.html b/tests/wpt/web-platform-tests/cookies/samesite/window-open-reload.https.html
index 9c30bd5ca67..ee2091b1373 100644
--- a/tests/wpt/web-platform-tests/cookies/samesite/window-open-reload.https.html
+++ b/tests/wpt/web-platform-tests/cookies/samesite/window-open-reload.https.html
@@ -34,7 +34,7 @@
             window.addEventListener("message", msgHandler);
 
             if (!w)
-              reject("Popup could not be opened (did you whitelist the test site in your popup blocker?).");
+              reject("Popup could not be opened (did you allow the test site in your popup blocker?).");
           });
         });
     }, title);
diff --git a/tests/wpt/web-platform-tests/cookies/samesite/window-open.https.html b/tests/wpt/web-platform-tests/cookies/samesite/window-open.https.html
index fe2318acc43..d685eb47fd0 100644
--- a/tests/wpt/web-platform-tests/cookies/samesite/window-open.https.html
+++ b/tests/wpt/web-platform-tests/cookies/samesite/window-open.https.html
@@ -28,7 +28,7 @@
             window.addEventListener("message", msgHandler);
 
             if (!w)
-              reject("Popup could not be opened (did you whitelist the test site in your popup blocker?).");
+              reject("Popup could not be opened (did you allow the test site in your popup blocker?).");
           });
         });
     }, title);
diff --git a/tests/wpt/web-platform-tests/css/css-flexbox/percentage-heights-010.html b/tests/wpt/web-platform-tests/css/css-flexbox/percentage-heights-010.html
new file mode 100644
index 00000000000..003cc2487ae
--- /dev/null
+++ b/tests/wpt/web-platform-tests/css/css-flexbox/percentage-heights-010.html
@@ -0,0 +1,13 @@
+<!DOCTYPE html>
+<title>A height: 100% descendant should trigger a relayout when stretching.</title>
+<link rel="help" href="https://drafts.csswg.org/css-flexbox-1/#definite-sizes" />
+<link rel="help" href="https://bugs.chromium.org/p/chromium/issues/detail?id=1043071" />
+<link rel="match" href="../reference/ref-filled-green-100px-square.xht" />
+<p>Test passes if there is a filled green square and <strong>no red</strong>.</p>
+<div style="display: flex; width: 100px;">
+  <div style="display: flex; flex-direction: column; flex: 1; min-height: 100px;">
+    <div style="flex: 1; background: red;">
+      <div style="height: 100%; background-color: green;"></div>
+    </div>
+  </div>
+</div>
diff --git a/tests/wpt/web-platform-tests/css/cssom-view/MediaQueryList-addListener-handleEvent.html b/tests/wpt/web-platform-tests/css/cssom-view/MediaQueryList-addListener-handleEvent.html
index 5bdd9dfc9ce..47267d98bba 100644
--- a/tests/wpt/web-platform-tests/css/cssom-view/MediaQueryList-addListener-handleEvent.html
+++ b/tests/wpt/web-platform-tests/css/cssom-view/MediaQueryList-addListener-handleEvent.html
@@ -71,36 +71,38 @@ promise_test(async t => {
     assert_equals(calls, 1);
 }, "doesn't look up handleEvent method on callable event listeners");
 
-const uncaught_error_test = async (t, listener) => {
+const uncaught_error_test = async (t, getHandleEvent) => {
     const mql = await createMQL(t);
-    mql.addListener(listener);
 
-    const eventWatcher = new EventWatcher(t, window, "error");
+    let calls = 0;
+    mql.addListener({
+        get handleEvent() {
+            calls++;
+            return getHandleEvent();
+        },
+    });
+
+    const eventWatcher = new EventWatcher(t, window, "error", waitForChangesReported);
     const errorPromise = eventWatcher.wait_for("error");
     triggerMQLEvent(mql);
 
     const event = await errorPromise;
+    assert_equals(calls, 1, "handleEvent property was not looked up");
     throw event.error;
 };
 
 promise_test(t => {
     const error = { name: "test" };
-    const listener = {
-        get handleEvent() {
-            throw error;
-        },
-    };
 
-    return promise_rejects_exactly(t, error, uncaught_error_test(t, listener));
+    return promise_rejects_exactly(t, error,
+        uncaught_error_test(t, () => { throw error; }));
 }, "rethrows errors when getting handleEvent");
 
 promise_test(t => {
-    const listener = { handleEvent: null };
-    return promise_rejects(t, new TypeError(), uncaught_error_test(t, listener));
+    return promise_rejects(t, new TypeError(), uncaught_error_test(t, () => false));
 }, "throws if handleEvent is falsy and not callable");
 
 promise_test(t => {
-    const listener = { handleEvent: "str" };
-    return promise_rejects(t, new TypeError(), uncaught_error_test(t, listener));
+    return promise_rejects(t, new TypeError(), uncaught_error_test(t, () => "str"));
 }, "throws if handleEvent is thruthy and not callable");
 </script>
diff --git a/tests/wpt/web-platform-tests/css/cssom/CSSStyleSheet.html b/tests/wpt/web-platform-tests/css/cssom/CSSStyleSheet.html
index 90cfb02751f..d38efc28023 100644
--- a/tests/wpt/web-platform-tests/css/cssom/CSSStyleSheet.html
+++ b/tests/wpt/web-platform-tests/css/cssom/CSSStyleSheet.html
@@ -45,7 +45,7 @@
     }, 'insertRule with #bar selector');
 
     test(function() {
-        assert_throws(new TypeError, function() { styleSheet.insertRule() });
+        assert_throws_js(TypeError, function() { styleSheet.insertRule() });
     }, 'insertRule with no argument throws');
 
     test(function() {
@@ -65,7 +65,7 @@
     }, 'deleteRule(1)');
 
     test(function() {
-        assert_throws(new TypeError, function() { styleSheet.deleteRule() });
+        assert_throws_js(TypeError, function() { styleSheet.deleteRule() });
     }, 'deleteRule with no argument throws');
 
     test(function() {
diff --git a/tests/wpt/web-platform-tests/css/cssom/medialist-interfaces-002.html b/tests/wpt/web-platform-tests/css/cssom/medialist-interfaces-002.html
index 9820015f5e0..210ace1393a 100644
--- a/tests/wpt/web-platform-tests/css/cssom/medialist-interfaces-002.html
+++ b/tests/wpt/web-platform-tests/css/cssom/medialist-interfaces-002.html
@@ -36,7 +36,7 @@
     // MediaList.deleteMedium called without argument throws error.
     test(function() {
       media_list = setup();
-      assert_throws(new TypeError, function() { media_list.deleteMedium(); });
+      assert_throws_js(TypeError, function() { media_list.deleteMedium(); });
     }, "deleteMedium_called_without_argument");
 
     // MediaList.deleteMedium removes correct medium and updates corresponding properties.
diff --git a/tests/wpt/web-platform-tests/custom-elements/historical.html b/tests/wpt/web-platform-tests/custom-elements/historical.html
index 70981ce59c4..5a961b13ad7 100644
--- a/tests/wpt/web-platform-tests/custom-elements/historical.html
+++ b/tests/wpt/web-platform-tests/custom-elements/historical.html
@@ -17,7 +17,7 @@ test(() => {
     assert_false(element.hasAttribute('is'))
   } catch (e) {
     // If v1 is supported, then converting string to dictionary should throw.
-    assert_throws(new TypeError, function() { throw e })
+    assert_throws_js(TypeError, function() { throw e })
   }
 }, 'document.createElement(localName, "string") should not work')
 
@@ -29,7 +29,7 @@ test(() => {
     assert_false(element.hasAttribute('is'))
   } catch (e) {
     // If v1 is supported, then converting string to dictionary should throw.
-    assert_throws(new TypeError, function() { throw e })
+    assert_throws_js(TypeError, function() { throw e })
   }
 }, 'document.createElementNS(namespace, qualifiedName, "string") should not work')
 </script>
diff --git a/tests/wpt/web-platform-tests/dom/events/EventListener-handleEvent.html b/tests/wpt/web-platform-tests/dom/events/EventListener-handleEvent.html
index 1eb80ccb15f..27730b20c58 100644
--- a/tests/wpt/web-platform-tests/dom/events/EventListener-handleEvent.html
+++ b/tests/wpt/web-platform-tests/dom/events/EventListener-handleEvent.html
@@ -27,30 +27,6 @@ test(function(t) {
     target.dispatchEvent(new Event(type));
 }, "calls `handleEvent` method of `EventListener`");
 
-test(function(t) {
-    var type = "foo";
-    var target = document.createElement("div");
-    var thrownError = { name: "test" };
-    var uncaughtError;
-    var errorHandler = function(event) {
-        uncaughtError = event.error;
-    };
-
-    window.addEventListener("error", errorHandler);
-    t.add_cleanup(function() {
-        window.removeEventListener("error", errorHandler);
-    });
-
-    target.addEventListener(type, {
-        get handleEvent() {
-            throw thrownError;
-        },
-    });
-
-    target.dispatchEvent(new Event(type));
-    assert_equals(thrownError, uncaughtError);
-}, "rethrows errors when getting `handleEvent`");
-
 test(function(t) {
     var type = "foo";
     var target = document.createElement("div");
@@ -81,45 +57,46 @@ test(function(t) {
     assert_equals(calls, 1);
 }, "doesn't call `handleEvent` method on callable `EventListener`");
 
-test(function(t) {
-    var type = "foo";
-    var target = document.createElement("div");
-    var uncaughtError;
-    var errorHandler = function(event) {
-        uncaughtError = event.error;
+const uncaught_error_test = async (t, getHandleEvent) => {
+    const type = "foo";
+    const target = document.createElement("div");
+
+    let calls = 0;
+    target.addEventListener(type, {
+        get handleEvent() {
+            calls++;
+            return getHandleEvent();
+        },
+    });
+
+    const timeout = () => {
+        return new Promise(resolve => {
+            t.step_timeout(resolve, 0);
+        });
     };
 
-    window.addEventListener("error", errorHandler);
-    t.add_cleanup(function() {
-        window.removeEventListener("error", errorHandler);
-    });
-
-    target.addEventListener(type, {
-        handleEvent: null,
-    });
+    const eventWatcher = new EventWatcher(t, window, "error", timeout);
+    const errorPromise = eventWatcher.wait_for("error");
 
     target.dispatchEvent(new Event(type));
-    assert_true(uncaughtError instanceof TypeError);
+
+    const event = await errorPromise;
+    assert_equals(calls, 1, "handleEvent property was not looked up");
+    throw event.error;
+};
+
+promise_test(t => {
+    const error = { name: "test" };
+
+    return promise_rejects_exactly(t, error,
+        uncaught_error_test(t, () => { throw error; }));
+}, "rethrows errors when getting `handleEvent`");
+
+promise_test(t => {
+    return promise_rejects(t, new TypeError(), uncaught_error_test(t, () => null));
 }, "throws if `handleEvent` is falsy and not callable");
 
-test(function(t) {
-    var type = "foo";
-    var target = document.createElement("div");
-    var uncaughtError;
-    var errorHandler = function(event) {
-        uncaughtError = event.error;
-    };
-
-    window.addEventListener("error", errorHandler);
-    t.add_cleanup(function() {
-        window.removeEventListener("error", errorHandler);
-    });
-
-    target.addEventListener(type, {
-        handleEvent: 1,
-    });
-
-    target.dispatchEvent(new Event(type));
-    assert_true(uncaughtError instanceof TypeError);
+promise_test(t => {
+    return promise_rejects(t, new TypeError(), uncaught_error_test(t, () => 42));
 }, "throws if `handleEvent` is thruthy and not callable");
 </script>
diff --git a/tests/wpt/web-platform-tests/encoding/textdecoder-fatal.any.js b/tests/wpt/web-platform-tests/encoding/textdecoder-fatal.any.js
index 5884f11ec3c..ba8aa5d06c3 100644
--- a/tests/wpt/web-platform-tests/encoding/textdecoder-fatal.any.js
+++ b/tests/wpt/web-platform-tests/encoding/textdecoder-fatal.any.js
@@ -71,7 +71,7 @@ test(() => {
   assert_equals(decoder.decode(new DataView(bytes.buffer, 0, 3)),
                 '♥',
                 'decode() should decode full sequence');
-  assert_throws(new TypeError,
+  assert_throws_js(TypeError,
                 () => decoder.decode(new DataView(bytes.buffer, 0, 2)),
                 'decode() should throw on incomplete sequence');
   assert_equals(decoder.decode(new DataView(bytes.buffer, 0, 3)),
diff --git a/tests/wpt/web-platform-tests/fetch/api/basic/keepalive.html b/tests/wpt/web-platform-tests/fetch/api/basic/keepalive.html
index 5316410004a..447ef2ddfec 100644
--- a/tests/wpt/web-platform-tests/fetch/api/basic/keepalive.html
+++ b/tests/wpt/web-platform-tests/fetch/api/basic/keepalive.html
@@ -7,25 +7,85 @@
 <script src="/common/get-host-info.sub.js"></script>
 <body>
 <script>
+function getUrl(origin1, origin2, withHeaders) {
+  const frameOrigin = host_info.HTTP_NOTSAMESITE_ORIGIN;
+  return `${frameOrigin}/fetch/api/resources/keepalive-iframe.html?` +
+    `origin1=${origin1}&` +
+    `origin2=${origin2}&` +
+    (withHeaders ? `with-headers` : ``);
+}
+
+async function getToken() {
+  return new Promise((resolve) => {
+    window.addEventListener('message', (event) => {
+      resolve(event.data);
+    }, {once: true});
+  });
+}
+
+async function queryToken(token) {
+  const response = await fetch(`../resources/stash-take.py?key=${token}`);
+  const json = await response.json();
+  return json;
+}
+
+// In order to parallelize the work, we are going to have an async_test
+// for the rest of the work. Note that we want the serialized behavior
+// for the steps so far, so we don't want to make the entire test case
+// an async_test.
+function checkToken(testName, token) {
+  async_test((test) => {
+    new Promise((resolve) => test.step_timeout(resolve, 1000)).then(() => {
+      return queryToken(token);
+    }).then((result) => {
+      assert_equals(result, 'on');
+    }).then(() => {
+      test.done();
+    }).catch(test.step_func((e) => {
+      assert_unreached(e);
+    }));
+  }, testName);
+}
+
 const host_info = get_host_info();
 promise_test(async (test) => {
   const iframe = document.createElement('iframe');
-  iframe.src = host_info.HTTP_REMOTE_ORIGIN +
-    '/fetch/api/resources/keepalive-iframe.html';
+  iframe.src = getUrl('', '', false);
   document.body.appendChild(iframe);
-  const uuid_promise = new Promise((resolve) => {
-    window.addEventListener('message', (event) => {
-      resolve(event.data);
-    });
-  });
+  const tokenPromise = getToken();
   await (new Promise((resolve) => iframe.addEventListener('load', resolve)));
-  const uuid = await uuid_promise;
+  const token = await tokenPromise;
   iframe.remove();
-  await (new Promise((resolve) => test.step_timeout(resolve, 1000)));
-  const response = await fetch(`../resources/stash-take.py?key=${uuid}`);
-  const json = await response.json();
-  assert_equals(json, 'on');
-});
+
+  checkToken('same-origin', token);
+}, 'same-origin; setting up');
+
+promise_test(async (test) => {
+  const iframe = document.createElement('iframe');
+  iframe.src = getUrl(host_info.HTTP_REMOTE_ORIGIN,
+                      host_info.HTTP_REMOTE_ORIGIN_WITH_DIFFERENT_PORT, false);
+  document.body.appendChild(iframe);
+  const tokenPromise = getToken();
+  await (new Promise((resolve) => iframe.addEventListener('load', resolve)));
+  const token = await tokenPromise;
+  iframe.remove();
+
+  checkToken('cross-origin redirect', token);
+}, 'cross-origin redirect; setting up');
+
+promise_test(async (test) => {
+  const iframe = document.createElement('iframe');
+  iframe.src = getUrl(host_info.HTTP_REMOTE_ORIGIN,
+                      host_info.HTTP_REMOTE_ORIGIN_WITH_DIFFERENT_PORT, true);
+  document.body.appendChild(iframe);
+  const tokenPromise = getToken();
+  await (new Promise((resolve) => iframe.addEventListener('load', resolve)));
+  const token = await tokenPromise;
+  iframe.remove();
+
+  checkToken('cross-origin redirect with preflight', token);
+}, 'cross-origin redirect with preflight; setting up');
+
 </script>
 </body>
 </html>
diff --git a/tests/wpt/web-platform-tests/fetch/api/headers/headers-record.html b/tests/wpt/web-platform-tests/fetch/api/headers/headers-record.html
index 85dfadd269d..34acc3b1c55 100644
--- a/tests/wpt/web-platform-tests/fetch/api/headers/headers-record.html
+++ b/tests/wpt/web-platform-tests/fetch/api/headers/headers-record.html
@@ -35,7 +35,7 @@ test(function() {
 }, "Passing undefined to Headers constructor");
 
 test(function() {
-  assert_throws(new TypeError, function() {
+  assert_throws_js(TypeError, function() {
     var h = new Headers(null);
   });
 }, "Passing null to Headers constructor");
@@ -126,7 +126,7 @@ test(function() {
   this.add_cleanup(clearLog);
   var record = { a: "b", "\uFFFF": "d" };
   var proxy = new Proxy(record, loggingHandler);
-  assert_throws(new TypeError, function() {
+  assert_throws_js(TypeError, function() {
     var h = new Headers(proxy);
   });
 
@@ -151,7 +151,7 @@ test(function() {
   this.add_cleanup(clearLog);
   var record = { a: "\uFFFF", c: "d" }
   var proxy = new Proxy(record, loggingHandler);
-  assert_throws(new TypeError, function() {
+  assert_throws_js(TypeError, function() {
     var h = new Headers(proxy);
   });
 
diff --git a/tests/wpt/web-platform-tests/fetch/api/resources/keepalive-iframe.html b/tests/wpt/web-platform-tests/fetch/api/resources/keepalive-iframe.html
index 742309ab4d2..47de0da7790 100644
--- a/tests/wpt/web-platform-tests/fetch/api/resources/keepalive-iframe.html
+++ b/tests/wpt/web-platform-tests/fetch/api/resources/keepalive-iframe.html
@@ -2,16 +2,24 @@
 <html>
 <meta charset="utf-8">
 <script src="/common/utils.js"></script>
+<script src="/common/get-host-info.sub.js"></script>
 <script>
-const uuid = token();
-const URL =
-    `../resources/redirect.py?` +
-    `delay=100&` +
-    `location=../resources/stash-put.py?key=${uuid}%26value=on`;
+const SEARCH_PARAMS = new URL(location.href).searchParams;
+const ORIGIN1 = SEARCH_PARAMS.get('origin1') || '';
+const ORIGIN2 = SEARCH_PARAMS.get('origin2') || '';
+const WITH_HEADERS = !!SEARCH_PARAMS.has('with-headers');
+const TOKEN = token();
+
+const url =
+    `${ORIGIN1}/fetch/api/resources/redirect.py?` +
+    `delay=500&` +
+    `allow_headers=foo&` +
+    `location=${ORIGIN2}/fetch/api/resources/stash-put.py?key=${TOKEN}%26value=on`;
 
 addEventListener('load', () => {
-  let p = fetch(URL, {keepalive: true});
-  window.parent.postMessage(uuid, '*');
+  const headers = WITH_HEADERS ? {'foo': 'bar'} : undefined;
+  let p = fetch(url, {keepalive: true, headers});
+  window.parent.postMessage(TOKEN, '*');
 });
 </script>
 </html>
diff --git a/tests/wpt/web-platform-tests/fetch/api/resources/stash-put.py b/tests/wpt/web-platform-tests/fetch/api/resources/stash-put.py
index dd84ff1fc85..36527b98b71 100644
--- a/tests/wpt/web-platform-tests/fetch/api/resources/stash-put.py
+++ b/tests/wpt/web-platform-tests/fetch/api/resources/stash-put.py
@@ -1,4 +1,11 @@
 def main(request, response):
+    if request.method == 'OPTIONS':
+        # CORS preflight
+        response.headers.set('Access-Control-Allow-Origin', '*')
+        response.headers.set('Access-Control-Allow-Methods', '*')
+        response.headers.set('Access-Control-Allow-Headers', '*')
+        return 'done'
+
     url_dir = '/'.join(request.url_parts.path.split('/')[:-1]) + '/'
     key = request.GET.first("key")
     value = request.GET.first("value")
diff --git a/tests/wpt/web-platform-tests/fetch/corb/script-resource-with-nonsniffable-types.tentative.sub.html b/tests/wpt/web-platform-tests/fetch/corb/script-resource-with-nonsniffable-types.tentative.sub.html
index 917e54984f4..255ff1da267 100644
--- a/tests/wpt/web-platform-tests/fetch/corb/script-resource-with-nonsniffable-types.tentative.sub.html
+++ b/tests/wpt/web-platform-tests/fetch/corb/script-resource-with-nonsniffable-types.tentative.sub.html
@@ -63,6 +63,7 @@ protected_mime_types = [
   "application/x-protobuf",
   "application/zip",
   "multipart/byteranges",
+  "multipart/signed",
   "text/csv",
   "text/event-stream",
 ]
diff --git a/tests/wpt/web-platform-tests/generic-sensor/SensorErrorEvent-constructor.https.html b/tests/wpt/web-platform-tests/generic-sensor/SensorErrorEvent-constructor.https.html
index 6e2d1684f57..2d68dec56d9 100644
--- a/tests/wpt/web-platform-tests/generic-sensor/SensorErrorEvent-constructor.https.html
+++ b/tests/wpt/web-platform-tests/generic-sensor/SensorErrorEvent-constructor.https.html
@@ -6,7 +6,7 @@
 <script>
   test(() => {
     assert_equals(SensorErrorEvent.length, 2);
-    assert_throws(new TypeError, () => new SensorErrorEvent('error'));
+    assert_throws_js(TypeError, () => new SensorErrorEvent('error'));
   }, 'SensorErrorEvent constructor without init dict');
 
   test(() => {
diff --git a/tests/wpt/web-platform-tests/html/browsers/origin/cross-origin-objects/cross-origin-objects.html b/tests/wpt/web-platform-tests/html/browsers/origin/cross-origin-objects/cross-origin-objects.html
index f16a18d639c..2c92d5e51ad 100644
--- a/tests/wpt/web-platform-tests/html/browsers/origin/cross-origin-objects/cross-origin-objects.html
+++ b/tests/wpt/web-platform-tests/html/browsers/origin/cross-origin-objects/cross-origin-objects.html
@@ -135,7 +135,7 @@ function addPromiseThenTest(func, desc) {
 }
 
 /*
- * Basic sanity testing.
+ * Basic smoke tests for same-origin and cross-origin behaviors.
  */
 
 addTest(function(win) {
@@ -154,14 +154,14 @@ addTest(function(win) {
 }, "Basic sanity-checking");
 
 /*
- * Whitelist behavior.
+ * Tests regarding which properties are allowed cross-origin.
  *
  * Also tests for [[GetOwnProperty]] and [[HasOwnProperty]] behavior.
  */
 
-var whitelistedSymbols = [Symbol.toStringTag, Symbol.hasInstance,
+var allowedSymbols = [Symbol.toStringTag, Symbol.hasInstance,
                           Symbol.isConcatSpreadable];
-var windowWhitelists = {
+var windowAllowlists = {
   namedFrames: ['donotleakme'],
   indices: ['0', '1'],
   getters: ['location', 'window', 'frames', 'self', 'top', 'parent',
@@ -174,22 +174,22 @@ var windowWhitelists = {
   // otherwise throw. They are not, however, cross-origin accessible.
   promiseMethods: ['createImageBitmap', 'fetch'],
 }
-windowWhitelists.propNames = Array.from(new Set([...windowWhitelists.indices,
-                                                 ...windowWhitelists.getters,
-                                                 ...windowWhitelists.setters,
-                                                 ...windowWhitelists.methods,
+windowAllowlists.propNames = Array.from(new Set([...windowAllowlists.indices,
+                                                 ...windowAllowlists.getters,
+                                                 ...windowAllowlists.setters,
+                                                 ...windowAllowlists.methods,
                                                  'then'])).sort();
-windowWhitelists.props = windowWhitelists.propNames.concat(whitelistedSymbols);
+windowAllowlists.props = windowAllowlists.propNames.concat(allowedSymbols);
 
-var locationWhitelists = {
+var locationAllowlists = {
   getters: [],
   setters: ['href'],
   methods: ['replace'],
   promiseMethods: [],
 }
-locationWhitelists.propNames = Array.from(new Set([...locationWhitelists.getters,
-                                                   ...locationWhitelists.setters,
-                                                   ...locationWhitelists.methods,
+locationAllowlists.propNames = Array.from(new Set([...locationAllowlists.getters,
+                                                   ...locationAllowlists.setters,
+                                                   ...locationAllowlists.methods,
                                                    'then'])).sort();
 
 // Define various sets of arguments to call cross-origin methods with. Arguments
@@ -216,7 +216,7 @@ var methodArgs = new Map(Object.entries({
 
 addTest(function(win) {
   for (var prop in window) {
-    if (windowWhitelists.props.indexOf(prop) != -1) {
+    if (windowAllowlists.props.indexOf(prop) != -1) {
       win[prop]; // Shouldn't throw.
       Object.getOwnPropertyDescriptor(win, prop); // Shouldn't throw.
       assert_true(Object.prototype.hasOwnProperty.call(win, prop), "hasOwnProperty for " + String(prop));
@@ -230,7 +230,7 @@ addTest(function(win) {
     if (prop != 'location')
       assert_throws("SecurityError", function() { win[prop] = undefined; }, "Should throw when writing to " + prop + " on Window");
   }
-  for (var prop of windowWhitelists.namedFrames) {
+  for (var prop of windowAllowlists.namedFrames) {
     win[prop]; // Shouldn't throw.
     Object.getOwnPropertyDescriptor(win, prop); // Shouldn't throw.
     assert_true(Object.prototype.hasOwnProperty.call(win, prop), "hasOwnProperty for " + String(prop));
@@ -257,10 +257,10 @@ addTest(function(win) {
       assert_throws("SecurityError", function() { win.location[prop] = undefined; }, "Should throw when writing to " + prop + " on Location");
     }
   }
-}, "Only whitelisted properties are accessible cross-origin");
+}, "Only certain properties are accessible cross-origin");
 
 addPromiseTest(async function(win, test_obj) {
-  async function checkProperties(objName, whitelists) {
+  async function checkProperties(objName, allowedlists) {
     var localObj = window[objName];
     var otherObj = win[objName];
 
@@ -273,10 +273,10 @@ addPromiseTest(async function(win, test_obj) {
 
       if ("value" in desc) {
         if (typeof desc.value === "function" && String(desc.value).includes("[native code]")) {
-          if (whitelists.promiseMethods.includes(prop)) {
+          if (allowedlists.promiseMethods.includes(prop)) {
             await promise_rejects(test_obj, "SecurityError", desc.value.call(otherObj),
                                   `Should throw when calling ${objName}.${prop} with cross-origin this object`);
-          } else if (!whitelists.methods.includes(prop)) {
+          } else if (!allowedlists.methods.includes(prop)) {
             for (let args of methodArgs.get(prop) || [[]]) {
               assert_throws("SecurityError", desc.value.bind(otherObj, ...args),
                             `Should throw when calling ${objName}.${prop} with cross-origin this object`);
@@ -290,7 +290,7 @@ addPromiseTest(async function(win, test_obj) {
         }
       } else {
         if (desc.get) {
-          if (whitelists.getters.includes(prop)) {
+          if (allowedlists.getters.includes(prop)) {
             desc.get.call(otherObj); // Shouldn't throw.
           } else {
             assert_throws("SecurityError", desc.get.bind(otherObj),
@@ -298,7 +298,7 @@ addPromiseTest(async function(win, test_obj) {
           }
         }
         if (desc.set) {
-          if (whitelists.setters.includes(prop)) {
+          if (allowedlists.setters.includes(prop)) {
             desc.set.call(otherObj, "javascript:undefined"); // Shouldn't throw.
           } else {
             assert_throws("SecurityError", desc.set.bind(otherObj, "foo"),
@@ -309,9 +309,9 @@ addPromiseTest(async function(win, test_obj) {
     }
   }
 
-  await checkProperties("location", locationWhitelists);
-  await checkProperties("window", windowWhitelists);
-}, "Only whitelisted properties are usable as cross-origin this objects");
+  await checkProperties("location", locationAllowlists);
+  await checkProperties("window", windowAllowlists);
+}, "Only certain properties are usable as cross-origin this objects");
 
 /*
  * ES Internal Methods.
@@ -341,8 +341,8 @@ addTest(function(win) {
   if (Object.setPrototypeOf)
     setters.push(function(p) { Object.setPrototypeOf(this, p); });
   setters.forEach(function(protoSetter) {
-    assert_throws(new TypeError, function() { protoSetter.call(win, new Object()); }, "proto setter |call| on cross-origin Window");
-    assert_throws(new TypeError, function() { protoSetter.call(win.location, new Object()); }, "proto setter |call| on cross-origin Location");
+    assert_throws_js(TypeError, function() { protoSetter.call(win, new Object()); }, "proto setter |call| on cross-origin Window");
+    assert_throws_js(TypeError, function() { protoSetter.call(win.location, new Object()); }, "proto setter |call| on cross-origin Location");
   });
   // Hack to avoid "duplicate test name" harness issues.
   setters.forEach(function(protoSetter) {
@@ -375,9 +375,9 @@ addTest(function(win) {
  * [[PreventExtensions]]
  */
 addTest(function(win) {
-  assert_throws(new TypeError, function() { Object.preventExtensions(win) },
+  assert_throws_js(TypeError, function() { Object.preventExtensions(win) },
                 "preventExtensions on cross-origin Window should throw");
-  assert_throws(new TypeError, function() { Object.preventExtensions(win.location) },
+  assert_throws_js(TypeError, function() { Object.preventExtensions(win.location) },
                 "preventExtensions on cross-origin Location should throw");
 }, "[[PreventExtensions]] should throw for cross-origin objects");
 
@@ -418,14 +418,14 @@ function checkPropertyDescriptor(desc, propName, expectWritable) {
 }
 
 addTest(function(win) {
-  windowWhitelists.props.forEach(function(prop) {
+  windowAllowlists.props.forEach(function(prop) {
     var desc = Object.getOwnPropertyDescriptor(win, prop);
     checkPropertyDescriptor(desc, prop, prop == 'location');
   });
   checkPropertyDescriptor(Object.getOwnPropertyDescriptor(win.location, 'replace'), 'replace', false);
   checkPropertyDescriptor(Object.getOwnPropertyDescriptor(win.location, 'href'), 'href', true);
   assert_equals(typeof Object.getOwnPropertyDescriptor(win.location, 'href').get, 'undefined', "Cross-origin location should have no href getter");
-  whitelistedSymbols.forEach(function(prop) {
+  allowedSymbols.forEach(function(prop) {
     var desc = Object.getOwnPropertyDescriptor(win.location, prop);
     checkPropertyDescriptor(desc, prop, false);
   });
@@ -494,9 +494,9 @@ addTest(function(win) {
   let i = 0;
   for (var prop in win) {
     i++;
-    assert_true(windowWhitelists.indices.includes(prop), prop + " is not safelisted for a cross-origin Window");
+    assert_true(windowAllowlists.indices.includes(prop), prop + " is not safelisted for a cross-origin Window");
   }
-  assert_equals(i, windowWhitelists.indices.length, "Enumerate all enumerable safelisted cross-origin Window properties");
+  assert_equals(i, windowAllowlists.indices.length, "Enumerate all enumerable safelisted cross-origin Window properties");
   i = 0;
   for (var prop in win.location) {
     i++;
@@ -510,48 +510,48 @@ addTest(function(win) {
 
 addTest(function(win) {
   assert_array_equals(Object.getOwnPropertyNames(win).sort(),
-                      windowWhitelists.propNames,
+                      windowAllowlists.propNames,
                       "Object.getOwnPropertyNames() gives the right answer for cross-origin Window");
   assert_array_equals(Object.keys(win).sort(),
-                      windowWhitelists.indices,
+                      windowAllowlists.indices,
                       "Object.keys() gives the right answer for cross-origin Window");
   assert_array_equals(Object.getOwnPropertyNames(win.location).sort(),
-                      locationWhitelists.propNames,
+                      locationAllowlists.propNames,
                       "Object.getOwnPropertyNames() gives the right answer for cross-origin Location");
   assert_equals(Object.keys(win.location).length, 0,
                       "Object.keys() gives the right answer for cross-origin Location");
 }, "[[OwnPropertyKeys]] should return all properties from cross-origin objects");
 
 addTest(function(win) {
-  assert_array_equals(Object.getOwnPropertySymbols(win), whitelistedSymbols,
+  assert_array_equals(Object.getOwnPropertySymbols(win), allowedSymbols,
     "Object.getOwnPropertySymbols() should return the three symbol-named properties that are exposed on a cross-origin Window");
   assert_array_equals(Object.getOwnPropertySymbols(win.location),
-                      whitelistedSymbols,
+                      allowedSymbols,
     "Object.getOwnPropertySymbols() should return the three symbol-named properties that are exposed on a cross-origin Location");
 }, "[[OwnPropertyKeys]] should return the right symbol-named properties for cross-origin objects");
 
 addTest(function(win) {
   var allWindowProps = Reflect.ownKeys(win);
-  indexedWindowProps = allWindowProps.slice(0, windowWhitelists.indices.length);
-  stringWindowProps = allWindowProps.slice(0, -1 * whitelistedSymbols.length);
-  symbolWindowProps = allWindowProps.slice(-1 * whitelistedSymbols.length);
+  indexedWindowProps = allWindowProps.slice(0, windowAllowlists.indices.length);
+  stringWindowProps = allWindowProps.slice(0, -1 * allowedSymbols.length);
+  symbolWindowProps = allWindowProps.slice(-1 * allowedSymbols.length);
   // stringWindowProps should have "then" last in this case.  Do this
   // check before we call stringWindowProps.sort() below.
   assert_equals(stringWindowProps[stringWindowProps.length - 1], "then",
                 "'then' property should be added to the end of the string list if not there");
-  assert_array_equals(indexedWindowProps, windowWhitelists.indices,
+  assert_array_equals(indexedWindowProps, windowAllowlists.indices,
                       "Reflect.ownKeys should start with the indices exposed on the cross-origin window.");
-  assert_array_equals(stringWindowProps.sort(), windowWhitelists.propNames,
+  assert_array_equals(stringWindowProps.sort(), windowAllowlists.propNames,
                       "Reflect.ownKeys should continue with the cross-origin window properties for a cross-origin Window.");
-  assert_array_equals(symbolWindowProps, whitelistedSymbols,
+  assert_array_equals(symbolWindowProps, allowedSymbols,
                       "Reflect.ownKeys should end with the cross-origin symbols for a cross-origin Window.");
 
   var allLocationProps = Reflect.ownKeys(win.location);
-  stringLocationProps = allLocationProps.slice(0, -1 * whitelistedSymbols.length);
-  symbolLocationProps = allLocationProps.slice(-1 * whitelistedSymbols.length);
-  assert_array_equals(stringLocationProps.sort(), locationWhitelists.propNames,
+  stringLocationProps = allLocationProps.slice(0, -1 * allowedSymbols.length);
+  symbolLocationProps = allLocationProps.slice(-1 * allowedSymbols.length);
+  assert_array_equals(stringLocationProps.sort(), locationAllowlists.propNames,
                       "Reflect.ownKeys should start with the cross-origin window properties for a cross-origin Location.")
-  assert_array_equals(symbolLocationProps, whitelistedSymbols,
+  assert_array_equals(symbolLocationProps, allowedSymbols,
                       "Reflect.ownKeys should end with the cross-origin symbols for a cross-origin Location.")
 }, "[[OwnPropertyKeys]] should place the symbols after the property names after the subframe indices");
 
diff --git a/tests/wpt/web-platform-tests/html/cross-origin-embedder-policy/require-corp.https.html b/tests/wpt/web-platform-tests/html/cross-origin-embedder-policy/require-corp.https.html
index 49b2eb123b5..8747d29e934 100644
--- a/tests/wpt/web-platform-tests/html/cross-origin-embedder-policy/require-corp.https.html
+++ b/tests/wpt/web-platform-tests/html/cross-origin-embedder-policy/require-corp.https.html
@@ -131,4 +131,26 @@ promise_test(async t => {
 promise_test(t => {
   return promise_rejects(t, new TypeError(), fetch(get_host_info().HTTPS_REMOTE_ORIGIN+"/common/blank.html", {mode: "no-cors"}));
 }, `"require-corp" top-level: fetch() to response without CORP should fail`);
+
+promise_test(t => {
+  const w = window.open();
+  return promise_rejects(t, new TypeError(), w.fetch(get_host_info().HTTPS_REMOTE_ORIGIN+"/common/blank.html", {mode: "no-cors"}));
+}, `"require-corp" top-level: fetch() to response without CORP through a WindowProxy should fail`);
+
+async_test(t => {
+  let w = window.open();
+  const frame = w.document.createElement("iframe");
+  t.add_cleanup(() => w.close());
+  t.step_timeout(() => {
+    // Make sure the iframe didn't load. See
+    // https://github.com/whatwg/html/issues/125 for why a timeout is
+    // used here. Long term all network error handling should be similar
+    // and have a reliable event.
+    assert_equals(frame.contentDocument, null);
+    t.done();
+  }, 500);
+  frame.src = "/common/blank.html";
+  document.body.append(frame);
+  assert_equals(frame.contentDocument.body.localName, "body");
+}, `"require-corp" top-level: navigating an iframe to a page without CORP, through a WindowProxy, should fail`);
 </script>
diff --git a/tests/wpt/web-platform-tests/html/infrastructure/common-dom-interfaces/collections/htmlallcollection.html b/tests/wpt/web-platform-tests/html/infrastructure/common-dom-interfaces/collections/htmlallcollection.html
index e3e0778c97a..095931ad785 100644
--- a/tests/wpt/web-platform-tests/html/infrastructure/common-dom-interfaces/collections/htmlallcollection.html
+++ b/tests/wpt/web-platform-tests/html/infrastructure/common-dom-interfaces/collections/htmlallcollection.html
@@ -160,7 +160,7 @@ test(function() {
 
 test(function() {
   assert_equals(document.all.namedItem.length, 1);
-  assert_throws(new TypeError, function() {
+  assert_throws_js(TypeError, function() {
     document.all.namedItem();
   });
 }, "namedItem method with no argument");
diff --git a/tests/wpt/web-platform-tests/html/semantics/document-metadata/the-style-element/style_load_event.html b/tests/wpt/web-platform-tests/html/semantics/document-metadata/the-style-element/style_load_event.html
new file mode 100644
index 00000000000..911a088c2ab
--- /dev/null
+++ b/tests/wpt/web-platform-tests/html/semantics/document-metadata/the-style-element/style_load_event.html
@@ -0,0 +1,33 @@
+<!DOCTYPE html>
+<title>HTML Test: The style load event should fire when textContent is changed</title>
+<link rel="author" title="Mason Freed" href="mailto:masonfreed@chromium.org">
+<link rel="help" href="https://html.spec.whatwg.org/multipage/semantics.html#update-a-style-block">
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+
+<style id=target onload="load()">
+  .box { color:red; }
+</style>
+<div class='box'></div>
+<div id="log"></div>
+
+<script>
+  var loadCount = 0;
+  function load() { loadCount++; }
+
+  function styleLoad() {
+    return new Promise((resolve) => {
+      document.getElementById('target').addEventListener('load', () => {
+        resolve();
+      });
+    });
+  }
+
+  promise_test(async t => {
+    await styleLoad();
+    assert_equals(loadCount,1,"Style element should have loaded once by now");
+    target.textContent = `.box { color: green; }`;
+    await styleLoad();
+    assert_equals(loadCount,2,"Style element should fire the load event when textContent changes");
+  },"style load event should fire when textContent changed");
+</script>
diff --git a/tests/wpt/web-platform-tests/html/semantics/embedded-content/media-elements/track/track-element/track-cue-mutable.html b/tests/wpt/web-platform-tests/html/semantics/embedded-content/media-elements/track/track-element/track-cue-mutable.html
index 63c3018aa99..cb28f6591ce 100644
--- a/tests/wpt/web-platform-tests/html/semantics/embedded-content/media-elements/track/track-element/track-cue-mutable.html
+++ b/tests/wpt/web-platform-tests/html/semantics/embedded-content/media-elements/track/track-element/track-cue-mutable.html
@@ -52,7 +52,7 @@
                 // to the new value; if the new value is the string "auto",
                 // then it must be interpreted as the special value auto.
                 assert_equals(textCue.line, "auto");
-                assert_throws(new TypeError, function() { textCue.line = "gazonk"; });
+                assert_throws_js(TypeError, function() { textCue.line = "gazonk"; });
                 assert_equals(textCue.line, "auto");
                 textCue.line = 42;
                 assert_equals(textCue.line, 42);
diff --git a/tests/wpt/web-platform-tests/interfaces/IndexedDB.idl b/tests/wpt/web-platform-tests/interfaces/IndexedDB.idl
index 33925d61423..a66a245466e 100644
--- a/tests/wpt/web-platform-tests/interfaces/IndexedDB.idl
+++ b/tests/wpt/web-platform-tests/interfaces/IndexedDB.idl
@@ -67,7 +67,8 @@ interface IDBDatabase : EventTarget {
   readonly attribute DOMStringList objectStoreNames;
 
   [NewObject] IDBTransaction transaction((DOMString or sequence<DOMString>) storeNames,
-                                         optional IDBTransactionMode mode = "readonly");
+                                         optional IDBTransactionMode mode = "readonly",
+                                         optional IDBTransactionOptions options = {});
   void close();
 
   [NewObject] IDBObjectStore createObjectStore(
@@ -82,6 +83,12 @@ interface IDBDatabase : EventTarget {
   attribute EventHandler onversionchange;
 };
 
+enum IDBTransactionDurability { "default", "strict", "relaxed" };
+
+dictionary IDBTransactionOptions {
+  IDBTransactionDurability durability = "default";
+};
+
 dictionary IDBObjectStoreParameters {
   (DOMString or sequence<DOMString>)? keyPath = null;
   boolean autoIncrement = false;
diff --git a/tests/wpt/web-platform-tests/interfaces/native-file-system.idl b/tests/wpt/web-platform-tests/interfaces/native-file-system.idl
new file mode 100644
index 00000000000..f4679175c46
--- /dev/null
+++ b/tests/wpt/web-platform-tests/interfaces/native-file-system.idl
@@ -0,0 +1,92 @@
+// GENERATED CONTENT - DO NOT EDIT
+// Content was automatically extracted by Reffy into reffy-reports
+// (https://github.com/tidoust/reffy-reports)
+// Source: Native File System (https://wicg.github.io/native-file-system/)
+
+dictionary FileSystemHandlePermissionDescriptor {
+  boolean writable = false;
+};
+
+[Exposed=(Window,Worker), SecureContext, Serializable]
+interface FileSystemHandle {
+  readonly attribute boolean isFile;
+  readonly attribute boolean isDirectory;
+  readonly attribute USVString name;
+
+  Promise<PermissionState> queryPermission(optional FileSystemHandlePermissionDescriptor descriptor = {});
+  Promise<PermissionState> requestPermission(optional FileSystemHandlePermissionDescriptor descriptor = {});
+};
+
+dictionary FileSystemCreateWriterOptions {
+  boolean keepExistingData = false;
+};
+
+[Exposed=(Window,Worker), SecureContext, Serializable]
+interface FileSystemFileHandle : FileSystemHandle {
+  Promise<File> getFile();
+  Promise<FileSystemWriter> createWriter(optional FileSystemCreateWriterOptions options = {});
+};
+
+dictionary FileSystemGetFileOptions {
+  boolean create = false;
+};
+
+dictionary FileSystemGetDirectoryOptions {
+  boolean create = false;
+};
+
+dictionary FileSystemRemoveOptions {
+  boolean recursive = false;
+};
+
+[Exposed=(Window,Worker), SecureContext, Serializable]
+interface FileSystemDirectoryHandle : FileSystemHandle {
+  Promise<FileSystemFileHandle> getFile(USVString name, optional FileSystemGetFileOptions options = {});
+  Promise<FileSystemDirectoryHandle> getDirectory(USVString name, optional FileSystemGetDirectoryOptions options = {});
+
+  // This really returns an async iterable, but that is not yet expressable in WebIDL.
+  object getEntries();
+
+  Promise<void> removeEntry(USVString name, optional FileSystemRemoveOptions options = {});
+};
+
+[Exposed=(Window,Worker), SecureContext]
+interface FileSystemWriter {
+  Promise<void> write(unsigned long long position, (BufferSource or Blob or USVString) data);
+  Promise<void> truncate(unsigned long long size);
+  Promise<void> close();
+};
+
+enum ChooseFileSystemEntriesType { "open-file", "save-file", "open-directory" };
+
+dictionary ChooseFileSystemEntriesOptionsAccepts {
+  USVString description;
+  sequence<USVString> mimeTypes;
+  sequence<USVString> extensions;
+};
+
+dictionary ChooseFileSystemEntriesOptions {
+    ChooseFileSystemEntriesType type = "open-file";
+    boolean multiple = false;
+    sequence<ChooseFileSystemEntriesOptionsAccepts> accepts;
+    boolean excludeAcceptAllOption = false;
+};
+
+[SecureContext]
+partial interface Window {
+    Promise<(FileSystemHandle or sequence<FileSystemHandle>)>
+        chooseFileSystemEntries(optional ChooseFileSystemEntriesOptions options = {});
+};
+
+enum SystemDirectoryType {
+  "sandbox"
+};
+
+dictionary GetSystemDirectoryOptions {
+  required SystemDirectoryType type;
+};
+
+[SecureContext]
+partial interface FileSystemDirectoryHandle {
+  static Promise<FileSystemDirectoryHandle> getSystemDirectory(GetSystemDirectoryOptions options);
+};
diff --git a/tests/wpt/web-platform-tests/intersection-observer/document-scrolling-element-root.html b/tests/wpt/web-platform-tests/intersection-observer/document-scrolling-element-root.html
index 9996299312c..443ff2ed85f 100644
--- a/tests/wpt/web-platform-tests/intersection-observer/document-scrolling-element-root.html
+++ b/tests/wpt/web-platform-tests/intersection-observer/document-scrolling-element-root.html
@@ -28,18 +28,16 @@ iframe.onload = function() {
   runTestCycle(function() {
     assert_true(!!iframe, "iframe exists");
 
-    root = iframe.contentDocument.scrollingElement;
-    assert_true(!!root, "Root element exists.");
     target = iframe.contentDocument.getElementById("target");
     assert_true(!!target, "Target element exists.");
     var observer = new IntersectionObserver(function(changes) {
       entries = entries.concat(changes)
-    }, { root: root });
+    }, { root: iframe.contentDocument });
     observer.observe(target);
     entries = entries.concat(observer.takeRecords());
     assert_equals(entries.length, 0, "No initial notifications.");
     runTestCycle(step0, "First rAF.");
-  }, "Observer with explicit root which is the document's scrolling element.");
+  }, "Observer with explicit root which is the document.");
 };
 
 function step0() {
diff --git a/tests/wpt/web-platform-tests/js/behaviours/SetPrototypeOf-window.html b/tests/wpt/web-platform-tests/js/behaviours/SetPrototypeOf-window.html
index 0a6ec249fa3..f104ca107c5 100644
--- a/tests/wpt/web-platform-tests/js/behaviours/SetPrototypeOf-window.html
+++ b/tests/wpt/web-platform-tests/js/behaviours/SetPrototypeOf-window.html
@@ -6,26 +6,26 @@
 <div id="log"></div>
 <script>
 test(function() {
-  assert_throws(new TypeError, function() {
+  assert_throws_js(TypeError, function() {
     Object.setPrototypeOf(window, window);
   }, "Setting the prototype should throw");
 }, "Setting the prototype of a window to itself via setPrototypeOf");
 
 test(function() {
-  assert_throws(new TypeError, function() {
+  assert_throws_js(TypeError, function() {
     window.__proto__ = window;
   }, "Setting the prototype should throw");
 }, "Setting the prototype of a window to itself via __proto__");
 
 test(function() {
-  assert_throws(new TypeError, function() {
+  assert_throws_js(TypeError, function() {
     Object.setPrototypeOf(window, Object.create(window));
   }, "Setting the prototype should throw");
 }, "Setting the prototype of a window to something that has the window on " +
    "its proto chain via setPrototypeOf");
 
 test(function() {
-  assert_throws(new TypeError, function() {
+  assert_throws_js(TypeError, function() {
     window.__proto__ = Object.create(window);
   }, "Setting the prototype should throw");
 }, "Setting the prototype of a window to something that has the window on " +
diff --git a/tests/wpt/web-platform-tests/media-source/mediasource-duration-boundaryconditions.html b/tests/wpt/web-platform-tests/media-source/mediasource-duration-boundaryconditions.html
index b95e495cb1d..e5be9f18fc4 100644
--- a/tests/wpt/web-platform-tests/media-source/mediasource-duration-boundaryconditions.html
+++ b/tests/wpt/web-platform-tests/media-source/mediasource-duration-boundaryconditions.html
@@ -21,7 +21,7 @@
                   test.waitForExpectedEvents(function()
                   {
                       if (expectedError) {
-                          assert_throws(expectedError,
+                          assert_throws_js(expectedError,
                               function() { mediaSource.duration = testDurationValue; },
                               "mediaSource.duration assignment throws an exception for " + testDurationValue);
                           test.done();
@@ -50,14 +50,14 @@
           DurationBoundaryConditionTest(Number.MAX_VALUE, null, "Set duration to Number.MAX_VALUE");
           DurationBoundaryConditionTest(Number.MIN_VALUE, null, "Set duration to Number.MIN_VALUE");
           DurationBoundaryConditionTest(Number.MAX_VALUE - 1, null, "Set duration to Number.MAX_VALUE - 1");
-          DurationBoundaryConditionTest(Number.MIN_VALUE - 1, new TypeError(), "Set duration to Number.MIN_VALUE - 1");
+          DurationBoundaryConditionTest(Number.MIN_VALUE - 1, TypeError, "Set duration to Number.MIN_VALUE - 1");
           DurationBoundaryConditionTest(Number.POSITIVE_INFINITY, null, "Set duration to Number.POSITIVE_INFINITY");
-          DurationBoundaryConditionTest(Number.NEGATIVE_INFINITY, new TypeError(), "Set duration to Number.NEGATIVE_INFINITY");
-          DurationBoundaryConditionTest(-1 * Number.MAX_VALUE, new TypeError(), "Set duration to lowest value.");
-          DurationBoundaryConditionTest(-101.9, new TypeError(), "Set duration to a negative double.");
+          DurationBoundaryConditionTest(Number.NEGATIVE_INFINITY, TypeError, "Set duration to Number.NEGATIVE_INFINITY");
+          DurationBoundaryConditionTest(-1 * Number.MAX_VALUE, TypeError, "Set duration to lowest value.");
+          DurationBoundaryConditionTest(-101.9, TypeError, "Set duration to a negative double.");
           DurationBoundaryConditionTest(101.9, null, "Set duration to a positive double.");
           DurationBoundaryConditionTest(0, null, "Set duration to zero");
-          DurationBoundaryConditionTest(NaN, new TypeError(), "Set duration to NaN");
+          DurationBoundaryConditionTest(NaN, TypeError, "Set duration to NaN");
         </script>
     </body>
 </html>
diff --git a/tests/wpt/web-platform-tests/mediacapture-record/BlobEvent-constructor.html b/tests/wpt/web-platform-tests/mediacapture-record/BlobEvent-constructor.html
index 3bcf4296e68..66dc3404d78 100644
--- a/tests/wpt/web-platform-tests/mediacapture-record/BlobEvent-constructor.html
+++ b/tests/wpt/web-platform-tests/mediacapture-record/BlobEvent-constructor.html
@@ -6,25 +6,25 @@
 <script>
 test(function() {
   assert_equals(BlobEvent.length, 2);
-  assert_throws(new TypeError, function() {
+  assert_throws_js(TypeError, function() {
     new BlobEvent("type");
   });
-  assert_throws(new TypeError, function() {
+  assert_throws_js(TypeError, function() {
     new BlobEvent("type", null);
   });
-  assert_throws(new TypeError, function() {
+  assert_throws_js(TypeError, function() {
     new BlobEvent("type", undefined);
   });
 }, "The BlobEventInit dictionary is required");
 
 test(function() {
-  assert_throws(new TypeError, function() {
+  assert_throws_js(TypeError, function() {
     new BlobEvent("type", {});
   });
-  assert_throws(new TypeError, function() {
+  assert_throws_js(TypeError, function() {
     new BlobEvent("type", { data: null });
   });
-  assert_throws(new TypeError, function() {
+  assert_throws_js(TypeError, function() {
     new BlobEvent("type", { data: undefined });
   });
 }, "The BlobEventInit dictionary's data member is required.");
diff --git a/tests/wpt/web-platform-tests/mediacapture-streams/MediaStreamTrackEvent-constructor.https.html b/tests/wpt/web-platform-tests/mediacapture-streams/MediaStreamTrackEvent-constructor.https.html
index 8f5a543d8fb..4946cd71d81 100644
--- a/tests/wpt/web-platform-tests/mediacapture-streams/MediaStreamTrackEvent-constructor.https.html
+++ b/tests/wpt/web-platform-tests/mediacapture-streams/MediaStreamTrackEvent-constructor.https.html
@@ -6,25 +6,25 @@
 <script>
 test(function() {
   assert_equals(MediaStreamTrackEvent.length, 2);
-  assert_throws(new TypeError, function() {
+  assert_throws_js(TypeError, function() {
     new MediaStreamTrackEvent("type");
   });
-  assert_throws(new TypeError, function() {
+  assert_throws_js(TypeError, function() {
     new MediaStreamTrackEvent("type", null);
   });
-  assert_throws(new TypeError, function() {
+  assert_throws_js(TypeError, function() {
     new MediaStreamTrackEvent("type", undefined);
   });
 }, "The eventInitDict argument is required");
 
 test(function() {
-  assert_throws(new TypeError, function() {
+  assert_throws_js(TypeError, function() {
     new MediaStreamTrackEvent("type", {});
   });
-  assert_throws(new TypeError, function() {
+  assert_throws_js(TypeError, function() {
     new MediaStreamTrackEvent("type", { track: null });
   });
-  assert_throws(new TypeError, function() {
+  assert_throws_js(TypeError, function() {
     new MediaStreamTrackEvent("type", { track: undefined });
   });
 }, "The eventInitDict's track member is required.");
diff --git a/tests/wpt/web-platform-tests/mediasession/positionstate.html b/tests/wpt/web-platform-tests/mediasession/positionstate.html
index 2eab2986d45..9033a7be5ce 100644
--- a/tests/wpt/web-platform-tests/mediasession/positionstate.html
+++ b/tests/wpt/web-platform-tests/mediasession/positionstate.html
@@ -42,8 +42,8 @@ test(() => {
 }, 'Test setPositionState with zero duration');
 
 test(() => {
-  assert_throws(
-      new TypeError,
+  assert_throws_js(
+      TypeError,
       _ => {
         window.navigator.mediaSession.setPositionState({
           duration: 60.9,
@@ -54,8 +54,8 @@ test(() => {
 }, 'Test setPositionState throws a TypeError if playback rate is negative');
 
 test(() => {
-  assert_throws(
-      new TypeError,
+  assert_throws_js(
+      TypeError,
       _ => {
         window.navigator.mediaSession.setPositionState({
           duration: -1
@@ -64,8 +64,8 @@ test(() => {
 }, 'Test setPositionState throws a TypeError if duration is negative');
 
 test(() => {
-  assert_throws(
-      new TypeError,
+  assert_throws_js(
+      TypeError,
       _ => {
         window.navigator.mediaSession.setPositionState({
           duration: 10,
@@ -75,8 +75,8 @@ test(() => {
 }, 'Test setPositionState throws a TypeError if position is negative');
 
 test(() => {
-  assert_throws(
-      new TypeError,
+  assert_throws_js(
+      TypeError,
       _ => {
         window.navigator.mediaSession.setPositionState({
           duration: 10,
@@ -86,8 +86,8 @@ test(() => {
 }, 'Test setPositionState throws a TypeError if duration is less than position');
 
 test(() => {
-  assert_throws(
-      new TypeError,
+  assert_throws_js(
+      TypeError,
       _ => {
         window.navigator.mediaSession.setPositionState({
           duration: 60.9,
@@ -98,8 +98,8 @@ test(() => {
 }, 'Test setPositionState throws a TypeError if playback rate is zero');
 
 test(() => {
-  assert_throws(
-      new TypeError,
+  assert_throws_js(
+      TypeError,
       _ => {
         window.navigator.mediaSession.setPositionState({
           position: 10.1,
diff --git a/tests/wpt/web-platform-tests/mediasession/setactionhandler.html b/tests/wpt/web-platform-tests/mediasession/setactionhandler.html
index 6e1bb26c67a..8f1330f8289 100644
--- a/tests/wpt/web-platform-tests/mediasession/setactionhandler.html
+++ b/tests/wpt/web-platform-tests/mediasession/setactionhandler.html
@@ -16,8 +16,8 @@ test(function(t) {
 }, "Test that setActionHandler() can be executed for supported actions");
 
 test(function(t) {
-  assert_throws(
-      new TypeError,
+  assert_throws_js(
+      TypeError,
       _ => { window.navigator.mediaSession.setActionHandler("invalid", null); });
 }, "Test that setActionHandler() throws exception for unsupported actions");
 
diff --git a/tests/wpt/web-platform-tests/native-file-system/idlharness.https.any.js b/tests/wpt/web-platform-tests/native-file-system/idlharness.https.any.js
new file mode 100644
index 00000000000..567912ddd77
--- /dev/null
+++ b/tests/wpt/web-platform-tests/native-file-system/idlharness.https.any.js
@@ -0,0 +1,15 @@
+// META: script=/resources/WebIDLParser.js
+// META: script=/resources/idlharness.js
+
+'use strict';
+
+idl_test(
+  ['native-file-system'],
+  ['html', 'dom'],
+  idl_array => {
+    idl_array.add_objects({
+      // TODO: Add instances of FileSystemHandle, FileSystemFileHandle,
+      // FileSystemDirectoryHandle and FileSystemWriter.
+    });
+  }
+);
diff --git a/tests/wpt/web-platform-tests/payment-request/onpaymentmenthodchange-attribute.https.html b/tests/wpt/web-platform-tests/payment-request/onpaymentmethodchange-attribute.https.html
similarity index 100%
rename from tests/wpt/web-platform-tests/payment-request/onpaymentmenthodchange-attribute.https.html
rename to tests/wpt/web-platform-tests/payment-request/onpaymentmethodchange-attribute.https.html
diff --git a/tests/wpt/web-platform-tests/referrer-policy/4K+1/generic/spec_json.js b/tests/wpt/web-platform-tests/referrer-policy/4K+1/generic/spec_json.js
new file mode 100644
index 00000000000..39cd997338e
--- /dev/null
+++ b/tests/wpt/web-platform-tests/referrer-policy/4K+1/generic/spec_json.js
@@ -0,0 +1 @@
+var SPEC_JSON = {"selection_pattern": "%(source_context_list)s.%(delivery_type)s/%(delivery_value)s/%(subresource)s/%(origin)s.%(redirection)s.%(source_scheme)s", "test_file_path_pattern": "gen/%(source_context_list)s.%(delivery_type)s/%(delivery_value)s/%(subresource)s/%(origin)s.%(redirection)s.%(source_scheme)s.html", "test_description_template": "Referrer Policy: Expects %(expectation)s for %(subresource)s to %(origin)s origin and %(redirection)s redirection from %(source_scheme)s context.", "test_page_title_template": "Referrer-Policy: %(title)s", "specification": [{"name": "unset-referrer-policy", "title": "Referrer Policy is not explicitly defined", "description": "Check that referrer URL follows no-referrer-when-downgrade policy when no explicit Referrer Policy is set.", "specification_url": "https://w3c.github.io/webappsec-referrer-policy/#referrer-policies", "test_expansion": [{"name": "insecure-protocol", "expansion": "default", "source_scheme": "http", "source_context_list": "*", "delivery_type": "*", "delivery_value": null, "redirection": "*", "origin": ["same-http", "cross-http"], "subresource": "*", "expectation": "stripped-referrer"}, {"name": "upgrade-protocol", "expansion": "default", "source_scheme": "http", "source_context_list": "*", "delivery_type": "*", "delivery_value": null, "redirection": "*", "origin": ["same-https", "cross-https"], "subresource": "*", "expectation": "stripped-referrer"}, {"name": "downgrade-protocol", "expansion": "default", "source_scheme": "https", "source_context_list": "*", "delivery_type": "*", "delivery_value": null, "redirection": "*", "origin": ["same-http", "cross-http"], "subresource": "*", "expectation": "omitted"}, {"name": "secure-protocol", "expansion": "default", "source_scheme": "https", "source_context_list": "*", "delivery_type": "*", "delivery_value": null, "redirection": "*", "origin": ["same-https", "cross-https"], "subresource": "*", "expectation": "stripped-referrer"}]}, {"name": "no-referrer", "title": "Referrer Policy is set to 'no-referrer'", "description": "Check that sub-resource never gets the referrer URL.", "specification_url": "https://w3c.github.io/webappsec-referrer-policy/#referrer-policy-no-referrer", "test_expansion": [{"name": "generic", "expansion": "default", "source_scheme": "*", "source_context_list": "*", "delivery_type": "*", "delivery_value": "no-referrer", "redirection": "*", "origin": "*", "subresource": "*", "expectation": "omitted"}]}, {"name": "no-referrer-when-downgrade", "title": "Referrer Policy is set to 'no-referrer-when-downgrade'", "description": "Check that non a priori insecure subresource gets the full Referrer URL. A priori insecure subresource gets no referrer information.", "specification_url": "https://w3c.github.io/webappsec-referrer-policy/#referrer-policy-no-referrer-when-downgrade", "test_expansion": [{"name": "insecure-protocol", "expansion": "default", "source_scheme": "http", "source_context_list": "*", "delivery_type": "*", "delivery_value": "no-referrer-when-downgrade", "redirection": "*", "origin": ["same-http", "cross-http"], "subresource": "*", "expectation": "stripped-referrer"}, {"name": "upgrade-protocol", "expansion": "default", "source_scheme": "http", "source_context_list": "*", "delivery_type": "*", "delivery_value": "no-referrer-when-downgrade", "redirection": "*", "origin": ["same-https", "cross-https"], "subresource": "*", "expectation": "stripped-referrer"}, {"name": "downgrade-protocol", "expansion": "default", "source_scheme": "https", "source_context_list": "*", "delivery_type": "*", "delivery_value": "no-referrer-when-downgrade", "redirection": "*", "origin": ["same-http", "cross-http"], "subresource": "*", "expectation": "omitted"}, {"name": "secure-protocol", "expansion": "default", "source_scheme": "https", "source_context_list": "*", "delivery_type": "*", "delivery_value": "no-referrer-when-downgrade", "redirection": "*", "origin": ["same-https", "cross-https"], "subresource": "*", "expectation": "stripped-referrer"}]}, {"name": "origin", "title": "Referrer Policy is set to 'origin'", "description": "Check that all subresources in all casses get only the origin portion of the referrer URL.", "specification_url": "https://w3c.github.io/webappsec-referrer-policy/#referrer-policy-origin", "test_expansion": [{"name": "generic", "expansion": "default", "source_scheme": "*", "source_context_list": "*", "delivery_type": "*", "delivery_value": "origin", "redirection": "*", "origin": "*", "subresource": "*", "expectation": "origin"}]}, {"name": "same-origin", "title": "Referrer Policy is set to 'same-origin'", "description": "Check that cross-origin subresources get no referrer information and same-origin get the stripped referrer URL.", "specification_url": "https://w3c.github.io/webappsec-referrer-policy/#referrer-policy-same-origin", "test_expansion": [{"name": "same-origin-insecure", "expansion": "default", "source_scheme": "http", "source_context_list": "*", "delivery_type": "*", "delivery_value": "same-origin", "redirection": "*", "origin": "same-http", "subresource": "*", "expectation": "stripped-referrer"}, {"name": "same-origin-secure-default", "expansion": "default", "source_scheme": "https", "source_context_list": "*", "delivery_type": "*", "delivery_value": "same-origin", "redirection": "*", "origin": "same-https", "subresource": "*", "expectation": "stripped-referrer"}, {"name": "same-origin-insecure", "expansion": "override", "source_scheme": "*", "source_context_list": "*", "delivery_type": "*", "delivery_value": "same-origin", "redirection": "swap-origin", "origin": ["same-http", "same-https"], "subresource": "*", "expectation": "omitted"}, {"name": "cross-origin", "expansion": "default", "source_scheme": "*", "source_context_list": "*", "delivery_type": "*", "delivery_value": "same-origin", "redirection": "*", "origin": ["cross-http", "cross-https"], "subresource": "*", "expectation": "omitted"}]}, {"name": "origin-when-cross-origin", "title": "Referrer Policy is set to 'origin-when-cross-origin'", "description": "Check that cross-origin subresources get the origin portion of the referrer URL and same-origin get the stripped referrer URL.", "specification_url": "https://w3c.github.io/webappsec-referrer-policy/#referrer-policy-origin-when-cross-origin", "test_expansion": [{"name": "same-origin-insecure", "expansion": "default", "source_scheme": "http", "source_context_list": "*", "delivery_type": "*", "delivery_value": "origin-when-cross-origin", "redirection": "*", "origin": "same-http", "subresource": "*", "expectation": "stripped-referrer"}, {"name": "same-origin-secure-default", "expansion": "default", "source_scheme": "https", "source_context_list": "*", "delivery_type": "*", "delivery_value": "origin-when-cross-origin", "redirection": "*", "origin": "same-https", "subresource": "*", "expectation": "stripped-referrer"}, {"name": "same-origin-upgrade", "expansion": "default", "source_scheme": "http", "source_context_list": "*", "delivery_type": "*", "delivery_value": "origin-when-cross-origin", "redirection": "*", "origin": "same-https", "subresource": "*", "expectation": "origin"}, {"name": "same-origin-downgrade", "expansion": "default", "source_scheme": "https", "source_context_list": "*", "delivery_type": "*", "delivery_value": "origin-when-cross-origin", "redirection": "*", "origin": "same-http", "subresource": "*", "expectation": "origin"}, {"name": "same-origin-insecure", "expansion": "override", "source_scheme": "*", "source_context_list": "*", "delivery_type": "*", "delivery_value": "origin-when-cross-origin", "redirection": "swap-origin", "origin": ["same-http", "same-https"], "subresource": "*", "expectation": "origin"}, {"name": "cross-origin", "expansion": "default", "source_scheme": "*", "source_context_list": "*", "delivery_type": "*", "delivery_value": "origin-when-cross-origin", "redirection": "*", "origin": ["cross-http", "cross-https"], "subresource": "*", "expectation": "origin"}]}, {"name": "strict-origin", "title": "Referrer Policy is set to 'strict-origin'", "description": "Check that non a priori insecure subresource gets only the origin portion of the referrer URL. A priori insecure subresource gets no referrer information.", "specification_url": "https://w3c.github.io/webappsec-referrer-policy/#referrer-policy-strict-origin", "test_expansion": [{"name": "insecure-protocol", "expansion": "default", "source_scheme": "http", "source_context_list": "*", "delivery_type": "*", "delivery_value": "strict-origin", "redirection": "*", "origin": ["same-http", "cross-http"], "subresource": "*", "expectation": "origin"}, {"name": "upgrade-protocol", "expansion": "default", "source_scheme": "http", "source_context_list": "*", "delivery_type": "*", "delivery_value": "strict-origin", "redirection": "*", "origin": ["same-https", "cross-https"], "subresource": "*", "expectation": "origin"}, {"name": "downgrade-protocol", "expansion": "default", "source_scheme": "https", "source_context_list": "*", "delivery_type": "*", "delivery_value": "strict-origin", "redirection": "*", "origin": ["same-http", "cross-http"], "subresource": "*", "expectation": "omitted"}, {"name": "secure-protocol", "expansion": "default", "source_scheme": "https", "source_context_list": "*", "delivery_type": "*", "delivery_value": "strict-origin", "redirection": "*", "origin": ["same-https", "cross-https"], "subresource": "*", "expectation": "origin"}]}, {"name": "strict-origin-when-cross-origin", "title": "Referrer Policy is set to 'strict-origin-when-cross-origin'", "description": "Check that a priori insecure subresource gets no referrer information. Otherwise, cross-origin subresources get the origin portion of the referrer URL and same-origin get the stripped referrer URL.", "specification_url": "https://w3c.github.io/webappsec-referrer-policy/#referrer-policy-strict-origin-when-cross-origin", "test_expansion": [{"name": "same-insecure", "expansion": "default", "source_scheme": "http", "source_context_list": "*", "delivery_type": "*", "delivery_value": "strict-origin-when-cross-origin", "redirection": "*", "origin": "same-http", "subresource": "*", "expectation": "stripped-referrer"}, {"name": "same-insecure", "expansion": "override", "source_scheme": "http", "source_context_list": "*", "delivery_type": "*", "delivery_value": "strict-origin-when-cross-origin", "redirection": "swap-origin", "origin": "same-http", "subresource": "*", "expectation": "origin"}, {"name": "cross-insecure", "expansion": "default", "source_scheme": "http", "source_context_list": "*", "delivery_type": "*", "delivery_value": "strict-origin-when-cross-origin", "redirection": "*", "origin": "cross-http", "subresource": "*", "expectation": "origin"}, {"name": "upgrade-protocol", "expansion": "default", "source_scheme": "http", "source_context_list": "*", "delivery_type": "*", "delivery_value": "strict-origin-when-cross-origin", "redirection": "*", "origin": ["same-https", "cross-https"], "subresource": "*", "expectation": "origin"}, {"name": "downgrade-protocol", "expansion": "default", "source_scheme": "https", "source_context_list": "*", "delivery_type": "*", "delivery_value": "strict-origin-when-cross-origin", "redirection": "*", "origin": ["same-http", "cross-http"], "subresource": "*", "expectation": "omitted"}, {"name": "same-secure", "expansion": "default", "source_scheme": "https", "source_context_list": "*", "delivery_type": "*", "delivery_value": "strict-origin-when-cross-origin", "redirection": "*", "origin": "same-https", "subresource": "*", "expectation": "stripped-referrer"}, {"name": "same-secure", "expansion": "override", "source_scheme": "https", "source_context_list": "*", "delivery_type": "*", "delivery_value": "strict-origin-when-cross-origin", "redirection": "swap-origin", "origin": "same-https", "subresource": "*", "expectation": "origin"}, {"name": "cross-secure", "expansion": "default", "source_scheme": "https", "source_context_list": "*", "delivery_type": "*", "delivery_value": "strict-origin-when-cross-origin", "redirection": "*", "origin": "cross-https", "subresource": "*", "expectation": "origin"}]}, {"name": "unsafe-url", "title": "Referrer Policy is set to 'unsafe-url'", "description": "Check that all sub-resources get the stripped referrer URL.", "specification_url": "https://w3c.github.io/webappsec-referrer-policy/#referrer-policy-unsafe-url", "test_expansion": [{"name": "generic", "expansion": "default", "source_scheme": "*", "source_context_list": "*", "delivery_type": "*", "delivery_value": "unsafe-url", "redirection": "*", "origin": "*", "subresource": "*", "expectation": "stripped-referrer"}]}], "delivery_key": "referrerPolicy", "excluded_tests": [{"name": "cross-origin-workers", "expansion": "*", "source_scheme": "*", "source_context_list": "*", "redirection": "*", "delivery_type": "*", "delivery_value": "*", "origin": ["cross-http", "cross-https"], "subresource": ["worker-classic", "worker-module", "sharedworker-classic"], "expectation": "*"}, {"name": "upgraded-protocol-workers", "expansion": "*", "source_scheme": "http", "source_context_list": "*", "delivery_type": "*", "delivery_value": "*", "redirection": "*", "origin": ["same-https", "cross-https"], "subresource": ["worker-classic", "worker-module", "sharedworker-classic"], "expectation": "*"}, {"name": "mixed-content-insecure-subresources", "expansion": "*", "source_scheme": "https", "source_context_list": "*", "delivery_type": "*", "delivery_value": "*", "redirection": "*", "origin": ["same-http", "cross-http"], "subresource": "*", "expectation": "*"}, {"name": "area-tag", "expansion": "*", "source_scheme": "*", "source_context_list": "*", "delivery_type": "*", "delivery_value": "*", "redirection": "*", "origin": "*", "subresource": "area-tag", "expectation": "*"}, {"name": "worker-requests-with-swap-origin-redirect", "expansion": "*", "source_scheme": "*", "source_context_list": "*", "delivery_type": "*", "delivery_value": "*", "redirection": "swap-origin", "origin": "*", "subresource": ["worker-classic", "worker-module", "sharedworker-classic"], "expectation": "*"}, {"name": "overhead-for-redirection", "expansion": "*", "source_scheme": "*", "source_context_list": "*", "delivery_type": "*", "delivery_value": "*", "redirection": ["keep-origin", "swap-origin"], "origin": "*", "subresource": ["a-tag", "area-tag"], "expectation": "*"}, {"name": "source-https-unsupported-by-web-platform-tests-runners", "expansion": "*", "source_scheme": "https", "source_context_list": "*", "delivery_type": "*", "delivery_value": "*", "redirection": "*", "origin": "*", "subresource": "*", "expectation": "*"}, {"name": "<link rel=noreferrer>'s delivery_value should be no-referrer", "expansion": "*", "source_scheme": "*", "source_context_list": "*", "delivery_type": "rel-noref", "delivery_value": [null, "no-referrer-when-downgrade", "same-origin", "origin", "origin-when-cross-origin", "strict-origin", "strict-origin-when-cross-origin", "unsafe-url"], "redirection": "*", "origin": "*", "subresource": "*", "expectation": "*"}, {"name": "expectation=stripped-referrer only", "expansion": "*", "source_scheme": "*", "source_context_list": "*", "redirection": "*", "delivery_type": "*", "delivery_value": "*", "origin": "*", "subresource": "*", "expectation": ["omitted", "origin"]}, {"name": "Only on the top context", "expansion": "*", "source_scheme": "*", "source_context_list": ["req", "srcdoc-inherit", "srcdoc", "iframe", "worker-classic", "worker-classic-data", "worker-module", "worker-module-data"], "redirection": "*", "delivery_type": "*", "delivery_value": "*", "origin": "*", "subresource": "*", "expectation": "*"}], "source_context_schema": {"supported_delivery_type": {"top": ["meta", "http-rp"], "iframe": ["meta", "http-rp"], "iframe-blank": ["meta"], "srcdoc": ["meta"], "worker-classic": ["http-rp"], "worker-module": ["http-rp"], "worker-classic-data": [], "worker-module-data": []}, "supported_subresource": {"top": "*", "iframe": "*", "iframe-blank": "*", "srcdoc": "*", "worker-classic": ["xhr", "fetch", "worker-classic", "worker-module"], "worker-module": ["xhr", "fetch", "worker-classic", "worker-module"], "worker-classic-data": ["xhr", "fetch"], "worker-module-data": ["xhr", "fetch"]}}, "subresource_schema": {"supported_delivery_type": {"iframe-tag": ["attr"], "img-tag": ["attr"], "script-tag": ["attr"], "a-tag": ["attr", "rel-noref"], "area-tag": ["attr"], "xhr": [], "fetch": [], "worker-module": [], "sharedworker-classic": [], "worker-classic": []}}, "source_context_list_schema": {"top": {"description": "Policy set by the top-level Document", "sourceContextList": [{"sourceContextType": "top", "policyDeliveries": ["policy"]}], "subresourcePolicyDeliveries": []}, "req": {"description": "Subresource request's policy should override Document's policy", "sourceContextList": [{"sourceContextType": "top", "policyDeliveries": ["anotherPolicy"]}], "subresourcePolicyDeliveries": ["nonNullPolicy"]}, "srcdoc-inherit": {"description": "srcdoc iframe should inherit parent Document's policy", "sourceContextList": [{"sourceContextType": "top", "policyDeliveries": ["policy"]}, {"sourceContextType": "srcdoc"}], "subresourcePolicyDeliveries": []}, "srcdoc": {"description": "srcdoc iframe's policy should override parent Document's policy", "sourceContextList": [{"sourceContextType": "top", "policyDeliveries": ["anotherPolicy"]}, {"sourceContextType": "srcdoc", "policyDeliveries": ["nonNullPolicy"]}], "subresourcePolicyDeliveries": []}, "iframe": {"description": "external iframe's policy should override parent Document's policy", "sourceContextList": [{"sourceContextType": "top", "policyDeliveries": ["anotherPolicy"]}, {"sourceContextType": "iframe", "policyDeliveries": ["policy"]}], "subresourcePolicyDeliveries": []}, "worker-classic": {"sourceContextList": [{"sourceContextType": "top", "policyDeliveries": ["anotherPolicy"]}, {"sourceContextType": "worker-classic", "policyDeliveries": ["policy"]}], "subresourcePolicyDeliveries": []}, "worker-classic-data": {"sourceContextList": [{"sourceContextType": "top", "policyDeliveries": ["anotherPolicy"]}, {"sourceContextType": "worker-classic-data", "policyDeliveries": ["policy"]}], "subresourcePolicyDeliveries": []}, "worker-module": {"sourceContextList": [{"sourceContextType": "top", "policyDeliveries": ["anotherPolicy"]}, {"sourceContextType": "worker-module", "policyDeliveries": ["policy"]}], "subresourcePolicyDeliveries": []}, "worker-module-data": {"sourceContextList": [{"sourceContextType": "top", "policyDeliveries": ["anotherPolicy"]}, {"sourceContextType": "worker-module-data", "policyDeliveries": ["policy"]}], "subresourcePolicyDeliveries": []}}, "test_expansion_schema": {"expansion": ["default", "override"], "delivery_type": ["attr", "rel-noref", "http-rp", "meta"], "delivery_value": [null, "no-referrer", "no-referrer-when-downgrade", "same-origin", "origin", "origin-when-cross-origin", "strict-origin", "strict-origin-when-cross-origin", "unsafe-url"], "origin": ["same-http", "same-https", "cross-http", "cross-https"], "source_context_list": ["top", "req", "srcdoc-inherit", "srcdoc", "iframe", "worker-classic", "worker-classic-data", "worker-module", "worker-module-data"], "source_scheme": ["http", "https"], "redirection": ["no-redirect", "keep-origin", "swap-origin"], "subresource": ["iframe-tag", "img-tag", "script-tag", "a-tag", "area-tag", "xhr", "worker-classic", "worker-module", "sharedworker-classic", "fetch"], "expectation": ["omitted", "origin", "stripped-referrer"]}};
diff --git a/tests/wpt/web-platform-tests/referrer-policy/4K+1/generic/test-case.sub.js b/tests/wpt/web-platform-tests/referrer-policy/4K+1/generic/test-case.sub.js
new file mode 100644
index 00000000000..b602d65f414
--- /dev/null
+++ b/tests/wpt/web-platform-tests/referrer-policy/4K+1/generic/test-case.sub.js
@@ -0,0 +1,11 @@
+function TestCase(scenario, testDescription, sanityChecker) {
+  // This check is A NOOP in release.
+  sanityChecker.checkScenario(scenario);
+  return {
+    start: () => runLengthTest(
+        scenario,
+        4096 + 1,
+        "origin",
+        "`Referer` header with length > 4k is stripped to an origin.")
+  };
+}
diff --git a/tests/wpt/web-platform-tests/referrer-policy/4K+1/spec.src.json b/tests/wpt/web-platform-tests/referrer-policy/4K+1/spec.src.json
new file mode 100644
index 00000000000..5dc2085c62f
--- /dev/null
+++ b/tests/wpt/web-platform-tests/referrer-policy/4K+1/spec.src.json
@@ -0,0 +1,40 @@
+{
+  "excluded_tests": [
+    {
+      "name": "expectation=stripped-referrer only",
+      "expansion": "*",
+      "source_scheme": "*",
+      "source_context_list": "*",
+      "redirection": "*",
+      "delivery_type": "*",
+      "delivery_value": "*",
+      "origin": "*",
+      "subresource": "*",
+      "expectation": [
+        "omitted",
+        "origin"
+      ]
+    },
+    {
+      "name": "Only on the top context",
+      "expansion": "*",
+      "source_scheme": "*",
+      "source_context_list": [
+        "req",
+        "srcdoc-inherit",
+        "srcdoc",
+        "iframe",
+        "worker-classic",
+        "worker-classic-data",
+        "worker-module",
+        "worker-module-data"
+      ],
+      "redirection": "*",
+      "delivery_type": "*",
+      "delivery_value": "*",
+      "origin": "*",
+      "subresource": "*",
+      "expectation": "*"
+    }
+  ]
+}
diff --git a/tests/wpt/web-platform-tests/referrer-policy/4K-1/generic/spec_json.js b/tests/wpt/web-platform-tests/referrer-policy/4K-1/generic/spec_json.js
new file mode 100644
index 00000000000..39cd997338e
--- /dev/null
+++ b/tests/wpt/web-platform-tests/referrer-policy/4K-1/generic/spec_json.js
@@ -0,0 +1 @@
+var SPEC_JSON = {"selection_pattern": "%(source_context_list)s.%(delivery_type)s/%(delivery_value)s/%(subresource)s/%(origin)s.%(redirection)s.%(source_scheme)s", "test_file_path_pattern": "gen/%(source_context_list)s.%(delivery_type)s/%(delivery_value)s/%(subresource)s/%(origin)s.%(redirection)s.%(source_scheme)s.html", "test_description_template": "Referrer Policy: Expects %(expectation)s for %(subresource)s to %(origin)s origin and %(redirection)s redirection from %(source_scheme)s context.", "test_page_title_template": "Referrer-Policy: %(title)s", "specification": [{"name": "unset-referrer-policy", "title": "Referrer Policy is not explicitly defined", "description": "Check that referrer URL follows no-referrer-when-downgrade policy when no explicit Referrer Policy is set.", "specification_url": "https://w3c.github.io/webappsec-referrer-policy/#referrer-policies", "test_expansion": [{"name": "insecure-protocol", "expansion": "default", "source_scheme": "http", "source_context_list": "*", "delivery_type": "*", "delivery_value": null, "redirection": "*", "origin": ["same-http", "cross-http"], "subresource": "*", "expectation": "stripped-referrer"}, {"name": "upgrade-protocol", "expansion": "default", "source_scheme": "http", "source_context_list": "*", "delivery_type": "*", "delivery_value": null, "redirection": "*", "origin": ["same-https", "cross-https"], "subresource": "*", "expectation": "stripped-referrer"}, {"name": "downgrade-protocol", "expansion": "default", "source_scheme": "https", "source_context_list": "*", "delivery_type": "*", "delivery_value": null, "redirection": "*", "origin": ["same-http", "cross-http"], "subresource": "*", "expectation": "omitted"}, {"name": "secure-protocol", "expansion": "default", "source_scheme": "https", "source_context_list": "*", "delivery_type": "*", "delivery_value": null, "redirection": "*", "origin": ["same-https", "cross-https"], "subresource": "*", "expectation": "stripped-referrer"}]}, {"name": "no-referrer", "title": "Referrer Policy is set to 'no-referrer'", "description": "Check that sub-resource never gets the referrer URL.", "specification_url": "https://w3c.github.io/webappsec-referrer-policy/#referrer-policy-no-referrer", "test_expansion": [{"name": "generic", "expansion": "default", "source_scheme": "*", "source_context_list": "*", "delivery_type": "*", "delivery_value": "no-referrer", "redirection": "*", "origin": "*", "subresource": "*", "expectation": "omitted"}]}, {"name": "no-referrer-when-downgrade", "title": "Referrer Policy is set to 'no-referrer-when-downgrade'", "description": "Check that non a priori insecure subresource gets the full Referrer URL. A priori insecure subresource gets no referrer information.", "specification_url": "https://w3c.github.io/webappsec-referrer-policy/#referrer-policy-no-referrer-when-downgrade", "test_expansion": [{"name": "insecure-protocol", "expansion": "default", "source_scheme": "http", "source_context_list": "*", "delivery_type": "*", "delivery_value": "no-referrer-when-downgrade", "redirection": "*", "origin": ["same-http", "cross-http"], "subresource": "*", "expectation": "stripped-referrer"}, {"name": "upgrade-protocol", "expansion": "default", "source_scheme": "http", "source_context_list": "*", "delivery_type": "*", "delivery_value": "no-referrer-when-downgrade", "redirection": "*", "origin": ["same-https", "cross-https"], "subresource": "*", "expectation": "stripped-referrer"}, {"name": "downgrade-protocol", "expansion": "default", "source_scheme": "https", "source_context_list": "*", "delivery_type": "*", "delivery_value": "no-referrer-when-downgrade", "redirection": "*", "origin": ["same-http", "cross-http"], "subresource": "*", "expectation": "omitted"}, {"name": "secure-protocol", "expansion": "default", "source_scheme": "https", "source_context_list": "*", "delivery_type": "*", "delivery_value": "no-referrer-when-downgrade", "redirection": "*", "origin": ["same-https", "cross-https"], "subresource": "*", "expectation": "stripped-referrer"}]}, {"name": "origin", "title": "Referrer Policy is set to 'origin'", "description": "Check that all subresources in all casses get only the origin portion of the referrer URL.", "specification_url": "https://w3c.github.io/webappsec-referrer-policy/#referrer-policy-origin", "test_expansion": [{"name": "generic", "expansion": "default", "source_scheme": "*", "source_context_list": "*", "delivery_type": "*", "delivery_value": "origin", "redirection": "*", "origin": "*", "subresource": "*", "expectation": "origin"}]}, {"name": "same-origin", "title": "Referrer Policy is set to 'same-origin'", "description": "Check that cross-origin subresources get no referrer information and same-origin get the stripped referrer URL.", "specification_url": "https://w3c.github.io/webappsec-referrer-policy/#referrer-policy-same-origin", "test_expansion": [{"name": "same-origin-insecure", "expansion": "default", "source_scheme": "http", "source_context_list": "*", "delivery_type": "*", "delivery_value": "same-origin", "redirection": "*", "origin": "same-http", "subresource": "*", "expectation": "stripped-referrer"}, {"name": "same-origin-secure-default", "expansion": "default", "source_scheme": "https", "source_context_list": "*", "delivery_type": "*", "delivery_value": "same-origin", "redirection": "*", "origin": "same-https", "subresource": "*", "expectation": "stripped-referrer"}, {"name": "same-origin-insecure", "expansion": "override", "source_scheme": "*", "source_context_list": "*", "delivery_type": "*", "delivery_value": "same-origin", "redirection": "swap-origin", "origin": ["same-http", "same-https"], "subresource": "*", "expectation": "omitted"}, {"name": "cross-origin", "expansion": "default", "source_scheme": "*", "source_context_list": "*", "delivery_type": "*", "delivery_value": "same-origin", "redirection": "*", "origin": ["cross-http", "cross-https"], "subresource": "*", "expectation": "omitted"}]}, {"name": "origin-when-cross-origin", "title": "Referrer Policy is set to 'origin-when-cross-origin'", "description": "Check that cross-origin subresources get the origin portion of the referrer URL and same-origin get the stripped referrer URL.", "specification_url": "https://w3c.github.io/webappsec-referrer-policy/#referrer-policy-origin-when-cross-origin", "test_expansion": [{"name": "same-origin-insecure", "expansion": "default", "source_scheme": "http", "source_context_list": "*", "delivery_type": "*", "delivery_value": "origin-when-cross-origin", "redirection": "*", "origin": "same-http", "subresource": "*", "expectation": "stripped-referrer"}, {"name": "same-origin-secure-default", "expansion": "default", "source_scheme": "https", "source_context_list": "*", "delivery_type": "*", "delivery_value": "origin-when-cross-origin", "redirection": "*", "origin": "same-https", "subresource": "*", "expectation": "stripped-referrer"}, {"name": "same-origin-upgrade", "expansion": "default", "source_scheme": "http", "source_context_list": "*", "delivery_type": "*", "delivery_value": "origin-when-cross-origin", "redirection": "*", "origin": "same-https", "subresource": "*", "expectation": "origin"}, {"name": "same-origin-downgrade", "expansion": "default", "source_scheme": "https", "source_context_list": "*", "delivery_type": "*", "delivery_value": "origin-when-cross-origin", "redirection": "*", "origin": "same-http", "subresource": "*", "expectation": "origin"}, {"name": "same-origin-insecure", "expansion": "override", "source_scheme": "*", "source_context_list": "*", "delivery_type": "*", "delivery_value": "origin-when-cross-origin", "redirection": "swap-origin", "origin": ["same-http", "same-https"], "subresource": "*", "expectation": "origin"}, {"name": "cross-origin", "expansion": "default", "source_scheme": "*", "source_context_list": "*", "delivery_type": "*", "delivery_value": "origin-when-cross-origin", "redirection": "*", "origin": ["cross-http", "cross-https"], "subresource": "*", "expectation": "origin"}]}, {"name": "strict-origin", "title": "Referrer Policy is set to 'strict-origin'", "description": "Check that non a priori insecure subresource gets only the origin portion of the referrer URL. A priori insecure subresource gets no referrer information.", "specification_url": "https://w3c.github.io/webappsec-referrer-policy/#referrer-policy-strict-origin", "test_expansion": [{"name": "insecure-protocol", "expansion": "default", "source_scheme": "http", "source_context_list": "*", "delivery_type": "*", "delivery_value": "strict-origin", "redirection": "*", "origin": ["same-http", "cross-http"], "subresource": "*", "expectation": "origin"}, {"name": "upgrade-protocol", "expansion": "default", "source_scheme": "http", "source_context_list": "*", "delivery_type": "*", "delivery_value": "strict-origin", "redirection": "*", "origin": ["same-https", "cross-https"], "subresource": "*", "expectation": "origin"}, {"name": "downgrade-protocol", "expansion": "default", "source_scheme": "https", "source_context_list": "*", "delivery_type": "*", "delivery_value": "strict-origin", "redirection": "*", "origin": ["same-http", "cross-http"], "subresource": "*", "expectation": "omitted"}, {"name": "secure-protocol", "expansion": "default", "source_scheme": "https", "source_context_list": "*", "delivery_type": "*", "delivery_value": "strict-origin", "redirection": "*", "origin": ["same-https", "cross-https"], "subresource": "*", "expectation": "origin"}]}, {"name": "strict-origin-when-cross-origin", "title": "Referrer Policy is set to 'strict-origin-when-cross-origin'", "description": "Check that a priori insecure subresource gets no referrer information. Otherwise, cross-origin subresources get the origin portion of the referrer URL and same-origin get the stripped referrer URL.", "specification_url": "https://w3c.github.io/webappsec-referrer-policy/#referrer-policy-strict-origin-when-cross-origin", "test_expansion": [{"name": "same-insecure", "expansion": "default", "source_scheme": "http", "source_context_list": "*", "delivery_type": "*", "delivery_value": "strict-origin-when-cross-origin", "redirection": "*", "origin": "same-http", "subresource": "*", "expectation": "stripped-referrer"}, {"name": "same-insecure", "expansion": "override", "source_scheme": "http", "source_context_list": "*", "delivery_type": "*", "delivery_value": "strict-origin-when-cross-origin", "redirection": "swap-origin", "origin": "same-http", "subresource": "*", "expectation": "origin"}, {"name": "cross-insecure", "expansion": "default", "source_scheme": "http", "source_context_list": "*", "delivery_type": "*", "delivery_value": "strict-origin-when-cross-origin", "redirection": "*", "origin": "cross-http", "subresource": "*", "expectation": "origin"}, {"name": "upgrade-protocol", "expansion": "default", "source_scheme": "http", "source_context_list": "*", "delivery_type": "*", "delivery_value": "strict-origin-when-cross-origin", "redirection": "*", "origin": ["same-https", "cross-https"], "subresource": "*", "expectation": "origin"}, {"name": "downgrade-protocol", "expansion": "default", "source_scheme": "https", "source_context_list": "*", "delivery_type": "*", "delivery_value": "strict-origin-when-cross-origin", "redirection": "*", "origin": ["same-http", "cross-http"], "subresource": "*", "expectation": "omitted"}, {"name": "same-secure", "expansion": "default", "source_scheme": "https", "source_context_list": "*", "delivery_type": "*", "delivery_value": "strict-origin-when-cross-origin", "redirection": "*", "origin": "same-https", "subresource": "*", "expectation": "stripped-referrer"}, {"name": "same-secure", "expansion": "override", "source_scheme": "https", "source_context_list": "*", "delivery_type": "*", "delivery_value": "strict-origin-when-cross-origin", "redirection": "swap-origin", "origin": "same-https", "subresource": "*", "expectation": "origin"}, {"name": "cross-secure", "expansion": "default", "source_scheme": "https", "source_context_list": "*", "delivery_type": "*", "delivery_value": "strict-origin-when-cross-origin", "redirection": "*", "origin": "cross-https", "subresource": "*", "expectation": "origin"}]}, {"name": "unsafe-url", "title": "Referrer Policy is set to 'unsafe-url'", "description": "Check that all sub-resources get the stripped referrer URL.", "specification_url": "https://w3c.github.io/webappsec-referrer-policy/#referrer-policy-unsafe-url", "test_expansion": [{"name": "generic", "expansion": "default", "source_scheme": "*", "source_context_list": "*", "delivery_type": "*", "delivery_value": "unsafe-url", "redirection": "*", "origin": "*", "subresource": "*", "expectation": "stripped-referrer"}]}], "delivery_key": "referrerPolicy", "excluded_tests": [{"name": "cross-origin-workers", "expansion": "*", "source_scheme": "*", "source_context_list": "*", "redirection": "*", "delivery_type": "*", "delivery_value": "*", "origin": ["cross-http", "cross-https"], "subresource": ["worker-classic", "worker-module", "sharedworker-classic"], "expectation": "*"}, {"name": "upgraded-protocol-workers", "expansion": "*", "source_scheme": "http", "source_context_list": "*", "delivery_type": "*", "delivery_value": "*", "redirection": "*", "origin": ["same-https", "cross-https"], "subresource": ["worker-classic", "worker-module", "sharedworker-classic"], "expectation": "*"}, {"name": "mixed-content-insecure-subresources", "expansion": "*", "source_scheme": "https", "source_context_list": "*", "delivery_type": "*", "delivery_value": "*", "redirection": "*", "origin": ["same-http", "cross-http"], "subresource": "*", "expectation": "*"}, {"name": "area-tag", "expansion": "*", "source_scheme": "*", "source_context_list": "*", "delivery_type": "*", "delivery_value": "*", "redirection": "*", "origin": "*", "subresource": "area-tag", "expectation": "*"}, {"name": "worker-requests-with-swap-origin-redirect", "expansion": "*", "source_scheme": "*", "source_context_list": "*", "delivery_type": "*", "delivery_value": "*", "redirection": "swap-origin", "origin": "*", "subresource": ["worker-classic", "worker-module", "sharedworker-classic"], "expectation": "*"}, {"name": "overhead-for-redirection", "expansion": "*", "source_scheme": "*", "source_context_list": "*", "delivery_type": "*", "delivery_value": "*", "redirection": ["keep-origin", "swap-origin"], "origin": "*", "subresource": ["a-tag", "area-tag"], "expectation": "*"}, {"name": "source-https-unsupported-by-web-platform-tests-runners", "expansion": "*", "source_scheme": "https", "source_context_list": "*", "delivery_type": "*", "delivery_value": "*", "redirection": "*", "origin": "*", "subresource": "*", "expectation": "*"}, {"name": "<link rel=noreferrer>'s delivery_value should be no-referrer", "expansion": "*", "source_scheme": "*", "source_context_list": "*", "delivery_type": "rel-noref", "delivery_value": [null, "no-referrer-when-downgrade", "same-origin", "origin", "origin-when-cross-origin", "strict-origin", "strict-origin-when-cross-origin", "unsafe-url"], "redirection": "*", "origin": "*", "subresource": "*", "expectation": "*"}, {"name": "expectation=stripped-referrer only", "expansion": "*", "source_scheme": "*", "source_context_list": "*", "redirection": "*", "delivery_type": "*", "delivery_value": "*", "origin": "*", "subresource": "*", "expectation": ["omitted", "origin"]}, {"name": "Only on the top context", "expansion": "*", "source_scheme": "*", "source_context_list": ["req", "srcdoc-inherit", "srcdoc", "iframe", "worker-classic", "worker-classic-data", "worker-module", "worker-module-data"], "redirection": "*", "delivery_type": "*", "delivery_value": "*", "origin": "*", "subresource": "*", "expectation": "*"}], "source_context_schema": {"supported_delivery_type": {"top": ["meta", "http-rp"], "iframe": ["meta", "http-rp"], "iframe-blank": ["meta"], "srcdoc": ["meta"], "worker-classic": ["http-rp"], "worker-module": ["http-rp"], "worker-classic-data": [], "worker-module-data": []}, "supported_subresource": {"top": "*", "iframe": "*", "iframe-blank": "*", "srcdoc": "*", "worker-classic": ["xhr", "fetch", "worker-classic", "worker-module"], "worker-module": ["xhr", "fetch", "worker-classic", "worker-module"], "worker-classic-data": ["xhr", "fetch"], "worker-module-data": ["xhr", "fetch"]}}, "subresource_schema": {"supported_delivery_type": {"iframe-tag": ["attr"], "img-tag": ["attr"], "script-tag": ["attr"], "a-tag": ["attr", "rel-noref"], "area-tag": ["attr"], "xhr": [], "fetch": [], "worker-module": [], "sharedworker-classic": [], "worker-classic": []}}, "source_context_list_schema": {"top": {"description": "Policy set by the top-level Document", "sourceContextList": [{"sourceContextType": "top", "policyDeliveries": ["policy"]}], "subresourcePolicyDeliveries": []}, "req": {"description": "Subresource request's policy should override Document's policy", "sourceContextList": [{"sourceContextType": "top", "policyDeliveries": ["anotherPolicy"]}], "subresourcePolicyDeliveries": ["nonNullPolicy"]}, "srcdoc-inherit": {"description": "srcdoc iframe should inherit parent Document's policy", "sourceContextList": [{"sourceContextType": "top", "policyDeliveries": ["policy"]}, {"sourceContextType": "srcdoc"}], "subresourcePolicyDeliveries": []}, "srcdoc": {"description": "srcdoc iframe's policy should override parent Document's policy", "sourceContextList": [{"sourceContextType": "top", "policyDeliveries": ["anotherPolicy"]}, {"sourceContextType": "srcdoc", "policyDeliveries": ["nonNullPolicy"]}], "subresourcePolicyDeliveries": []}, "iframe": {"description": "external iframe's policy should override parent Document's policy", "sourceContextList": [{"sourceContextType": "top", "policyDeliveries": ["anotherPolicy"]}, {"sourceContextType": "iframe", "policyDeliveries": ["policy"]}], "subresourcePolicyDeliveries": []}, "worker-classic": {"sourceContextList": [{"sourceContextType": "top", "policyDeliveries": ["anotherPolicy"]}, {"sourceContextType": "worker-classic", "policyDeliveries": ["policy"]}], "subresourcePolicyDeliveries": []}, "worker-classic-data": {"sourceContextList": [{"sourceContextType": "top", "policyDeliveries": ["anotherPolicy"]}, {"sourceContextType": "worker-classic-data", "policyDeliveries": ["policy"]}], "subresourcePolicyDeliveries": []}, "worker-module": {"sourceContextList": [{"sourceContextType": "top", "policyDeliveries": ["anotherPolicy"]}, {"sourceContextType": "worker-module", "policyDeliveries": ["policy"]}], "subresourcePolicyDeliveries": []}, "worker-module-data": {"sourceContextList": [{"sourceContextType": "top", "policyDeliveries": ["anotherPolicy"]}, {"sourceContextType": "worker-module-data", "policyDeliveries": ["policy"]}], "subresourcePolicyDeliveries": []}}, "test_expansion_schema": {"expansion": ["default", "override"], "delivery_type": ["attr", "rel-noref", "http-rp", "meta"], "delivery_value": [null, "no-referrer", "no-referrer-when-downgrade", "same-origin", "origin", "origin-when-cross-origin", "strict-origin", "strict-origin-when-cross-origin", "unsafe-url"], "origin": ["same-http", "same-https", "cross-http", "cross-https"], "source_context_list": ["top", "req", "srcdoc-inherit", "srcdoc", "iframe", "worker-classic", "worker-classic-data", "worker-module", "worker-module-data"], "source_scheme": ["http", "https"], "redirection": ["no-redirect", "keep-origin", "swap-origin"], "subresource": ["iframe-tag", "img-tag", "script-tag", "a-tag", "area-tag", "xhr", "worker-classic", "worker-module", "sharedworker-classic", "fetch"], "expectation": ["omitted", "origin", "stripped-referrer"]}};
diff --git a/tests/wpt/web-platform-tests/referrer-policy/4K-1/generic/test-case.sub.js b/tests/wpt/web-platform-tests/referrer-policy/4K-1/generic/test-case.sub.js
new file mode 100644
index 00000000000..5b6aa4216b7
--- /dev/null
+++ b/tests/wpt/web-platform-tests/referrer-policy/4K-1/generic/test-case.sub.js
@@ -0,0 +1,11 @@
+function TestCase(scenario, testDescription, sanityChecker) {
+  // This check is A NOOP in release.
+  sanityChecker.checkScenario(scenario);
+  return {
+    start: () => runLengthTest(
+        scenario,
+        4096 - 1,
+        scenario.expectation,
+        "`Referer` header with length < 4k is not stripped to an origin.")
+  };
+}
diff --git a/tests/wpt/web-platform-tests/referrer-policy/4K-1/spec.src.json b/tests/wpt/web-platform-tests/referrer-policy/4K-1/spec.src.json
new file mode 100644
index 00000000000..5dc2085c62f
--- /dev/null
+++ b/tests/wpt/web-platform-tests/referrer-policy/4K-1/spec.src.json
@@ -0,0 +1,40 @@
+{
+  "excluded_tests": [
+    {
+      "name": "expectation=stripped-referrer only",
+      "expansion": "*",
+      "source_scheme": "*",
+      "source_context_list": "*",
+      "redirection": "*",
+      "delivery_type": "*",
+      "delivery_value": "*",
+      "origin": "*",
+      "subresource": "*",
+      "expectation": [
+        "omitted",
+        "origin"
+      ]
+    },
+    {
+      "name": "Only on the top context",
+      "expansion": "*",
+      "source_scheme": "*",
+      "source_context_list": [
+        "req",
+        "srcdoc-inherit",
+        "srcdoc",
+        "iframe",
+        "worker-classic",
+        "worker-classic-data",
+        "worker-module",
+        "worker-module-data"
+      ],
+      "redirection": "*",
+      "delivery_type": "*",
+      "delivery_value": "*",
+      "origin": "*",
+      "subresource": "*",
+      "expectation": "*"
+    }
+  ]
+}
diff --git a/tests/wpt/web-platform-tests/referrer-policy/4K/generic/spec_json.js b/tests/wpt/web-platform-tests/referrer-policy/4K/generic/spec_json.js
new file mode 100644
index 00000000000..39cd997338e
--- /dev/null
+++ b/tests/wpt/web-platform-tests/referrer-policy/4K/generic/spec_json.js
@@ -0,0 +1 @@
+var SPEC_JSON = {"selection_pattern": "%(source_context_list)s.%(delivery_type)s/%(delivery_value)s/%(subresource)s/%(origin)s.%(redirection)s.%(source_scheme)s", "test_file_path_pattern": "gen/%(source_context_list)s.%(delivery_type)s/%(delivery_value)s/%(subresource)s/%(origin)s.%(redirection)s.%(source_scheme)s.html", "test_description_template": "Referrer Policy: Expects %(expectation)s for %(subresource)s to %(origin)s origin and %(redirection)s redirection from %(source_scheme)s context.", "test_page_title_template": "Referrer-Policy: %(title)s", "specification": [{"name": "unset-referrer-policy", "title": "Referrer Policy is not explicitly defined", "description": "Check that referrer URL follows no-referrer-when-downgrade policy when no explicit Referrer Policy is set.", "specification_url": "https://w3c.github.io/webappsec-referrer-policy/#referrer-policies", "test_expansion": [{"name": "insecure-protocol", "expansion": "default", "source_scheme": "http", "source_context_list": "*", "delivery_type": "*", "delivery_value": null, "redirection": "*", "origin": ["same-http", "cross-http"], "subresource": "*", "expectation": "stripped-referrer"}, {"name": "upgrade-protocol", "expansion": "default", "source_scheme": "http", "source_context_list": "*", "delivery_type": "*", "delivery_value": null, "redirection": "*", "origin": ["same-https", "cross-https"], "subresource": "*", "expectation": "stripped-referrer"}, {"name": "downgrade-protocol", "expansion": "default", "source_scheme": "https", "source_context_list": "*", "delivery_type": "*", "delivery_value": null, "redirection": "*", "origin": ["same-http", "cross-http"], "subresource": "*", "expectation": "omitted"}, {"name": "secure-protocol", "expansion": "default", "source_scheme": "https", "source_context_list": "*", "delivery_type": "*", "delivery_value": null, "redirection": "*", "origin": ["same-https", "cross-https"], "subresource": "*", "expectation": "stripped-referrer"}]}, {"name": "no-referrer", "title": "Referrer Policy is set to 'no-referrer'", "description": "Check that sub-resource never gets the referrer URL.", "specification_url": "https://w3c.github.io/webappsec-referrer-policy/#referrer-policy-no-referrer", "test_expansion": [{"name": "generic", "expansion": "default", "source_scheme": "*", "source_context_list": "*", "delivery_type": "*", "delivery_value": "no-referrer", "redirection": "*", "origin": "*", "subresource": "*", "expectation": "omitted"}]}, {"name": "no-referrer-when-downgrade", "title": "Referrer Policy is set to 'no-referrer-when-downgrade'", "description": "Check that non a priori insecure subresource gets the full Referrer URL. A priori insecure subresource gets no referrer information.", "specification_url": "https://w3c.github.io/webappsec-referrer-policy/#referrer-policy-no-referrer-when-downgrade", "test_expansion": [{"name": "insecure-protocol", "expansion": "default", "source_scheme": "http", "source_context_list": "*", "delivery_type": "*", "delivery_value": "no-referrer-when-downgrade", "redirection": "*", "origin": ["same-http", "cross-http"], "subresource": "*", "expectation": "stripped-referrer"}, {"name": "upgrade-protocol", "expansion": "default", "source_scheme": "http", "source_context_list": "*", "delivery_type": "*", "delivery_value": "no-referrer-when-downgrade", "redirection": "*", "origin": ["same-https", "cross-https"], "subresource": "*", "expectation": "stripped-referrer"}, {"name": "downgrade-protocol", "expansion": "default", "source_scheme": "https", "source_context_list": "*", "delivery_type": "*", "delivery_value": "no-referrer-when-downgrade", "redirection": "*", "origin": ["same-http", "cross-http"], "subresource": "*", "expectation": "omitted"}, {"name": "secure-protocol", "expansion": "default", "source_scheme": "https", "source_context_list": "*", "delivery_type": "*", "delivery_value": "no-referrer-when-downgrade", "redirection": "*", "origin": ["same-https", "cross-https"], "subresource": "*", "expectation": "stripped-referrer"}]}, {"name": "origin", "title": "Referrer Policy is set to 'origin'", "description": "Check that all subresources in all casses get only the origin portion of the referrer URL.", "specification_url": "https://w3c.github.io/webappsec-referrer-policy/#referrer-policy-origin", "test_expansion": [{"name": "generic", "expansion": "default", "source_scheme": "*", "source_context_list": "*", "delivery_type": "*", "delivery_value": "origin", "redirection": "*", "origin": "*", "subresource": "*", "expectation": "origin"}]}, {"name": "same-origin", "title": "Referrer Policy is set to 'same-origin'", "description": "Check that cross-origin subresources get no referrer information and same-origin get the stripped referrer URL.", "specification_url": "https://w3c.github.io/webappsec-referrer-policy/#referrer-policy-same-origin", "test_expansion": [{"name": "same-origin-insecure", "expansion": "default", "source_scheme": "http", "source_context_list": "*", "delivery_type": "*", "delivery_value": "same-origin", "redirection": "*", "origin": "same-http", "subresource": "*", "expectation": "stripped-referrer"}, {"name": "same-origin-secure-default", "expansion": "default", "source_scheme": "https", "source_context_list": "*", "delivery_type": "*", "delivery_value": "same-origin", "redirection": "*", "origin": "same-https", "subresource": "*", "expectation": "stripped-referrer"}, {"name": "same-origin-insecure", "expansion": "override", "source_scheme": "*", "source_context_list": "*", "delivery_type": "*", "delivery_value": "same-origin", "redirection": "swap-origin", "origin": ["same-http", "same-https"], "subresource": "*", "expectation": "omitted"}, {"name": "cross-origin", "expansion": "default", "source_scheme": "*", "source_context_list": "*", "delivery_type": "*", "delivery_value": "same-origin", "redirection": "*", "origin": ["cross-http", "cross-https"], "subresource": "*", "expectation": "omitted"}]}, {"name": "origin-when-cross-origin", "title": "Referrer Policy is set to 'origin-when-cross-origin'", "description": "Check that cross-origin subresources get the origin portion of the referrer URL and same-origin get the stripped referrer URL.", "specification_url": "https://w3c.github.io/webappsec-referrer-policy/#referrer-policy-origin-when-cross-origin", "test_expansion": [{"name": "same-origin-insecure", "expansion": "default", "source_scheme": "http", "source_context_list": "*", "delivery_type": "*", "delivery_value": "origin-when-cross-origin", "redirection": "*", "origin": "same-http", "subresource": "*", "expectation": "stripped-referrer"}, {"name": "same-origin-secure-default", "expansion": "default", "source_scheme": "https", "source_context_list": "*", "delivery_type": "*", "delivery_value": "origin-when-cross-origin", "redirection": "*", "origin": "same-https", "subresource": "*", "expectation": "stripped-referrer"}, {"name": "same-origin-upgrade", "expansion": "default", "source_scheme": "http", "source_context_list": "*", "delivery_type": "*", "delivery_value": "origin-when-cross-origin", "redirection": "*", "origin": "same-https", "subresource": "*", "expectation": "origin"}, {"name": "same-origin-downgrade", "expansion": "default", "source_scheme": "https", "source_context_list": "*", "delivery_type": "*", "delivery_value": "origin-when-cross-origin", "redirection": "*", "origin": "same-http", "subresource": "*", "expectation": "origin"}, {"name": "same-origin-insecure", "expansion": "override", "source_scheme": "*", "source_context_list": "*", "delivery_type": "*", "delivery_value": "origin-when-cross-origin", "redirection": "swap-origin", "origin": ["same-http", "same-https"], "subresource": "*", "expectation": "origin"}, {"name": "cross-origin", "expansion": "default", "source_scheme": "*", "source_context_list": "*", "delivery_type": "*", "delivery_value": "origin-when-cross-origin", "redirection": "*", "origin": ["cross-http", "cross-https"], "subresource": "*", "expectation": "origin"}]}, {"name": "strict-origin", "title": "Referrer Policy is set to 'strict-origin'", "description": "Check that non a priori insecure subresource gets only the origin portion of the referrer URL. A priori insecure subresource gets no referrer information.", "specification_url": "https://w3c.github.io/webappsec-referrer-policy/#referrer-policy-strict-origin", "test_expansion": [{"name": "insecure-protocol", "expansion": "default", "source_scheme": "http", "source_context_list": "*", "delivery_type": "*", "delivery_value": "strict-origin", "redirection": "*", "origin": ["same-http", "cross-http"], "subresource": "*", "expectation": "origin"}, {"name": "upgrade-protocol", "expansion": "default", "source_scheme": "http", "source_context_list": "*", "delivery_type": "*", "delivery_value": "strict-origin", "redirection": "*", "origin": ["same-https", "cross-https"], "subresource": "*", "expectation": "origin"}, {"name": "downgrade-protocol", "expansion": "default", "source_scheme": "https", "source_context_list": "*", "delivery_type": "*", "delivery_value": "strict-origin", "redirection": "*", "origin": ["same-http", "cross-http"], "subresource": "*", "expectation": "omitted"}, {"name": "secure-protocol", "expansion": "default", "source_scheme": "https", "source_context_list": "*", "delivery_type": "*", "delivery_value": "strict-origin", "redirection": "*", "origin": ["same-https", "cross-https"], "subresource": "*", "expectation": "origin"}]}, {"name": "strict-origin-when-cross-origin", "title": "Referrer Policy is set to 'strict-origin-when-cross-origin'", "description": "Check that a priori insecure subresource gets no referrer information. Otherwise, cross-origin subresources get the origin portion of the referrer URL and same-origin get the stripped referrer URL.", "specification_url": "https://w3c.github.io/webappsec-referrer-policy/#referrer-policy-strict-origin-when-cross-origin", "test_expansion": [{"name": "same-insecure", "expansion": "default", "source_scheme": "http", "source_context_list": "*", "delivery_type": "*", "delivery_value": "strict-origin-when-cross-origin", "redirection": "*", "origin": "same-http", "subresource": "*", "expectation": "stripped-referrer"}, {"name": "same-insecure", "expansion": "override", "source_scheme": "http", "source_context_list": "*", "delivery_type": "*", "delivery_value": "strict-origin-when-cross-origin", "redirection": "swap-origin", "origin": "same-http", "subresource": "*", "expectation": "origin"}, {"name": "cross-insecure", "expansion": "default", "source_scheme": "http", "source_context_list": "*", "delivery_type": "*", "delivery_value": "strict-origin-when-cross-origin", "redirection": "*", "origin": "cross-http", "subresource": "*", "expectation": "origin"}, {"name": "upgrade-protocol", "expansion": "default", "source_scheme": "http", "source_context_list": "*", "delivery_type": "*", "delivery_value": "strict-origin-when-cross-origin", "redirection": "*", "origin": ["same-https", "cross-https"], "subresource": "*", "expectation": "origin"}, {"name": "downgrade-protocol", "expansion": "default", "source_scheme": "https", "source_context_list": "*", "delivery_type": "*", "delivery_value": "strict-origin-when-cross-origin", "redirection": "*", "origin": ["same-http", "cross-http"], "subresource": "*", "expectation": "omitted"}, {"name": "same-secure", "expansion": "default", "source_scheme": "https", "source_context_list": "*", "delivery_type": "*", "delivery_value": "strict-origin-when-cross-origin", "redirection": "*", "origin": "same-https", "subresource": "*", "expectation": "stripped-referrer"}, {"name": "same-secure", "expansion": "override", "source_scheme": "https", "source_context_list": "*", "delivery_type": "*", "delivery_value": "strict-origin-when-cross-origin", "redirection": "swap-origin", "origin": "same-https", "subresource": "*", "expectation": "origin"}, {"name": "cross-secure", "expansion": "default", "source_scheme": "https", "source_context_list": "*", "delivery_type": "*", "delivery_value": "strict-origin-when-cross-origin", "redirection": "*", "origin": "cross-https", "subresource": "*", "expectation": "origin"}]}, {"name": "unsafe-url", "title": "Referrer Policy is set to 'unsafe-url'", "description": "Check that all sub-resources get the stripped referrer URL.", "specification_url": "https://w3c.github.io/webappsec-referrer-policy/#referrer-policy-unsafe-url", "test_expansion": [{"name": "generic", "expansion": "default", "source_scheme": "*", "source_context_list": "*", "delivery_type": "*", "delivery_value": "unsafe-url", "redirection": "*", "origin": "*", "subresource": "*", "expectation": "stripped-referrer"}]}], "delivery_key": "referrerPolicy", "excluded_tests": [{"name": "cross-origin-workers", "expansion": "*", "source_scheme": "*", "source_context_list": "*", "redirection": "*", "delivery_type": "*", "delivery_value": "*", "origin": ["cross-http", "cross-https"], "subresource": ["worker-classic", "worker-module", "sharedworker-classic"], "expectation": "*"}, {"name": "upgraded-protocol-workers", "expansion": "*", "source_scheme": "http", "source_context_list": "*", "delivery_type": "*", "delivery_value": "*", "redirection": "*", "origin": ["same-https", "cross-https"], "subresource": ["worker-classic", "worker-module", "sharedworker-classic"], "expectation": "*"}, {"name": "mixed-content-insecure-subresources", "expansion": "*", "source_scheme": "https", "source_context_list": "*", "delivery_type": "*", "delivery_value": "*", "redirection": "*", "origin": ["same-http", "cross-http"], "subresource": "*", "expectation": "*"}, {"name": "area-tag", "expansion": "*", "source_scheme": "*", "source_context_list": "*", "delivery_type": "*", "delivery_value": "*", "redirection": "*", "origin": "*", "subresource": "area-tag", "expectation": "*"}, {"name": "worker-requests-with-swap-origin-redirect", "expansion": "*", "source_scheme": "*", "source_context_list": "*", "delivery_type": "*", "delivery_value": "*", "redirection": "swap-origin", "origin": "*", "subresource": ["worker-classic", "worker-module", "sharedworker-classic"], "expectation": "*"}, {"name": "overhead-for-redirection", "expansion": "*", "source_scheme": "*", "source_context_list": "*", "delivery_type": "*", "delivery_value": "*", "redirection": ["keep-origin", "swap-origin"], "origin": "*", "subresource": ["a-tag", "area-tag"], "expectation": "*"}, {"name": "source-https-unsupported-by-web-platform-tests-runners", "expansion": "*", "source_scheme": "https", "source_context_list": "*", "delivery_type": "*", "delivery_value": "*", "redirection": "*", "origin": "*", "subresource": "*", "expectation": "*"}, {"name": "<link rel=noreferrer>'s delivery_value should be no-referrer", "expansion": "*", "source_scheme": "*", "source_context_list": "*", "delivery_type": "rel-noref", "delivery_value": [null, "no-referrer-when-downgrade", "same-origin", "origin", "origin-when-cross-origin", "strict-origin", "strict-origin-when-cross-origin", "unsafe-url"], "redirection": "*", "origin": "*", "subresource": "*", "expectation": "*"}, {"name": "expectation=stripped-referrer only", "expansion": "*", "source_scheme": "*", "source_context_list": "*", "redirection": "*", "delivery_type": "*", "delivery_value": "*", "origin": "*", "subresource": "*", "expectation": ["omitted", "origin"]}, {"name": "Only on the top context", "expansion": "*", "source_scheme": "*", "source_context_list": ["req", "srcdoc-inherit", "srcdoc", "iframe", "worker-classic", "worker-classic-data", "worker-module", "worker-module-data"], "redirection": "*", "delivery_type": "*", "delivery_value": "*", "origin": "*", "subresource": "*", "expectation": "*"}], "source_context_schema": {"supported_delivery_type": {"top": ["meta", "http-rp"], "iframe": ["meta", "http-rp"], "iframe-blank": ["meta"], "srcdoc": ["meta"], "worker-classic": ["http-rp"], "worker-module": ["http-rp"], "worker-classic-data": [], "worker-module-data": []}, "supported_subresource": {"top": "*", "iframe": "*", "iframe-blank": "*", "srcdoc": "*", "worker-classic": ["xhr", "fetch", "worker-classic", "worker-module"], "worker-module": ["xhr", "fetch", "worker-classic", "worker-module"], "worker-classic-data": ["xhr", "fetch"], "worker-module-data": ["xhr", "fetch"]}}, "subresource_schema": {"supported_delivery_type": {"iframe-tag": ["attr"], "img-tag": ["attr"], "script-tag": ["attr"], "a-tag": ["attr", "rel-noref"], "area-tag": ["attr"], "xhr": [], "fetch": [], "worker-module": [], "sharedworker-classic": [], "worker-classic": []}}, "source_context_list_schema": {"top": {"description": "Policy set by the top-level Document", "sourceContextList": [{"sourceContextType": "top", "policyDeliveries": ["policy"]}], "subresourcePolicyDeliveries": []}, "req": {"description": "Subresource request's policy should override Document's policy", "sourceContextList": [{"sourceContextType": "top", "policyDeliveries": ["anotherPolicy"]}], "subresourcePolicyDeliveries": ["nonNullPolicy"]}, "srcdoc-inherit": {"description": "srcdoc iframe should inherit parent Document's policy", "sourceContextList": [{"sourceContextType": "top", "policyDeliveries": ["policy"]}, {"sourceContextType": "srcdoc"}], "subresourcePolicyDeliveries": []}, "srcdoc": {"description": "srcdoc iframe's policy should override parent Document's policy", "sourceContextList": [{"sourceContextType": "top", "policyDeliveries": ["anotherPolicy"]}, {"sourceContextType": "srcdoc", "policyDeliveries": ["nonNullPolicy"]}], "subresourcePolicyDeliveries": []}, "iframe": {"description": "external iframe's policy should override parent Document's policy", "sourceContextList": [{"sourceContextType": "top", "policyDeliveries": ["anotherPolicy"]}, {"sourceContextType": "iframe", "policyDeliveries": ["policy"]}], "subresourcePolicyDeliveries": []}, "worker-classic": {"sourceContextList": [{"sourceContextType": "top", "policyDeliveries": ["anotherPolicy"]}, {"sourceContextType": "worker-classic", "policyDeliveries": ["policy"]}], "subresourcePolicyDeliveries": []}, "worker-classic-data": {"sourceContextList": [{"sourceContextType": "top", "policyDeliveries": ["anotherPolicy"]}, {"sourceContextType": "worker-classic-data", "policyDeliveries": ["policy"]}], "subresourcePolicyDeliveries": []}, "worker-module": {"sourceContextList": [{"sourceContextType": "top", "policyDeliveries": ["anotherPolicy"]}, {"sourceContextType": "worker-module", "policyDeliveries": ["policy"]}], "subresourcePolicyDeliveries": []}, "worker-module-data": {"sourceContextList": [{"sourceContextType": "top", "policyDeliveries": ["anotherPolicy"]}, {"sourceContextType": "worker-module-data", "policyDeliveries": ["policy"]}], "subresourcePolicyDeliveries": []}}, "test_expansion_schema": {"expansion": ["default", "override"], "delivery_type": ["attr", "rel-noref", "http-rp", "meta"], "delivery_value": [null, "no-referrer", "no-referrer-when-downgrade", "same-origin", "origin", "origin-when-cross-origin", "strict-origin", "strict-origin-when-cross-origin", "unsafe-url"], "origin": ["same-http", "same-https", "cross-http", "cross-https"], "source_context_list": ["top", "req", "srcdoc-inherit", "srcdoc", "iframe", "worker-classic", "worker-classic-data", "worker-module", "worker-module-data"], "source_scheme": ["http", "https"], "redirection": ["no-redirect", "keep-origin", "swap-origin"], "subresource": ["iframe-tag", "img-tag", "script-tag", "a-tag", "area-tag", "xhr", "worker-classic", "worker-module", "sharedworker-classic", "fetch"], "expectation": ["omitted", "origin", "stripped-referrer"]}};
diff --git a/tests/wpt/web-platform-tests/referrer-policy/4K/generic/test-case.sub.js b/tests/wpt/web-platform-tests/referrer-policy/4K/generic/test-case.sub.js
new file mode 100644
index 00000000000..912c06e10e7
--- /dev/null
+++ b/tests/wpt/web-platform-tests/referrer-policy/4K/generic/test-case.sub.js
@@ -0,0 +1,11 @@
+function TestCase(scenario, testDescription, sanityChecker) {
+  // This check is A NOOP in release.
+  sanityChecker.checkScenario(scenario);
+  return {
+    start: () => runLengthTest(
+        scenario,
+        4096,
+        scenario.expectation,
+        "`Referer` header with length == 4k is not stripped to an origin.")
+  };
+}
diff --git a/tests/wpt/web-platform-tests/referrer-policy/4K/spec.src.json b/tests/wpt/web-platform-tests/referrer-policy/4K/spec.src.json
new file mode 100644
index 00000000000..5dc2085c62f
--- /dev/null
+++ b/tests/wpt/web-platform-tests/referrer-policy/4K/spec.src.json
@@ -0,0 +1,40 @@
+{
+  "excluded_tests": [
+    {
+      "name": "expectation=stripped-referrer only",
+      "expansion": "*",
+      "source_scheme": "*",
+      "source_context_list": "*",
+      "redirection": "*",
+      "delivery_type": "*",
+      "delivery_value": "*",
+      "origin": "*",
+      "subresource": "*",
+      "expectation": [
+        "omitted",
+        "origin"
+      ]
+    },
+    {
+      "name": "Only on the top context",
+      "expansion": "*",
+      "source_scheme": "*",
+      "source_context_list": [
+        "req",
+        "srcdoc-inherit",
+        "srcdoc",
+        "iframe",
+        "worker-classic",
+        "worker-classic-data",
+        "worker-module",
+        "worker-module-data"
+      ],
+      "redirection": "*",
+      "delivery_type": "*",
+      "delivery_value": "*",
+      "origin": "*",
+      "subresource": "*",
+      "expectation": "*"
+    }
+  ]
+}
diff --git a/tests/wpt/web-platform-tests/referrer-policy/generic/test-case.sub.js b/tests/wpt/web-platform-tests/referrer-policy/generic/test-case.sub.js
index c8a6b139f33..a8292e57e1f 100644
--- a/tests/wpt/web-platform-tests/referrer-policy/generic/test-case.sub.js
+++ b/tests/wpt/web-platform-tests/referrer-policy/generic/test-case.sub.js
@@ -22,110 +22,77 @@ function invokeScenario(scenario) {
   return invokeRequest(subresource, scenario.source_context_list);
 }
 
+const referrerUrlResolver = {
+  "omitted": function(sourceUrl) {
+    return undefined;
+  },
+  "origin": function(sourceUrl) {
+    return new URL(sourceUrl).origin + "/";
+  },
+  "stripped-referrer": function(sourceUrl) {
+    return stripUrlForUseAsReferrer(sourceUrl);
+  }
+};
+
+function checkResult(scenario, expectation, result) {
+// https://w3c.github.io/webappsec-referrer-policy/#determine-requests-referrer
+  let referrerSource = result.sourceContextUrl;
+  const sentFromSrcdoc = scenario.source_context_list.length > 0 &&
+      scenario.source_context_list[scenario.source_context_list.length - 1]
+      .sourceContextType === 'srcdoc';
+  if (sentFromSrcdoc) {
+    // Step 3. While document is an iframe srcdoc document, let document be
+    // document's browsing context's browsing context container's node
+    // document. [spec text]
+
+    // Workaround for srcdoc cases. Currently we only test <iframe srcdoc>
+    // inside the top-level Document, so |document| in the spec here is
+    // the top-level Document.
+    // This doesn't work if e.g. we test <iframe srcdoc> inside another
+    // external <iframe>.
+    referrerSource = location.toString();
+  }
+  const expectedReferrerUrl =
+    referrerUrlResolver[expectation](referrerSource);
+
+  // Check the reported URL.
+  assert_equals(result.referrer,
+                expectedReferrerUrl,
+                "Reported Referrer URL is '" +
+                expectation + "'.");
+  assert_equals(result.headers.referer,
+                expectedReferrerUrl,
+                "Reported Referrer URL from HTTP header is '" +
+                expectedReferrerUrl + "'");
+}
+
+function runLengthTest(scenario, urlLength, expectation, testDescription) {
+  // `Referer` headers with length over 4k are culled down to an origin, so,
+  // let's test around that boundary for tests that would otherwise return
+  // the complete URL.
+  history.pushState(null, null, "/");
+  history.replaceState(null, null,
+      "A".repeat(urlLength - location.href.length));
+
+  promise_test(t => {
+    assert_equals(scenario.expectation, "stripped-referrer");
+    // Only on top-level Window, due to navigations using `history`.
+    assert_equals(scenario.source_context_list.length, 0);
+
+    return invokeScenario(scenario)
+      .then(result => checkResult(scenario, expectation, result));
+  }, testDescription);
+}
+
 function TestCase(scenario, testDescription, sanityChecker) {
   // This check is A NOOP in release.
   sanityChecker.checkScenario(scenario);
 
-  const referrerUrlResolver = {
-    "omitted": function(sourceUrl) {
-      return undefined;
-    },
-    "origin": function(sourceUrl) {
-      return new URL(sourceUrl).origin + "/";
-    },
-    "stripped-referrer": function(sourceUrl) {
-      return stripUrlForUseAsReferrer(sourceUrl);
-    }
-  };
-
-  const checkResult = (expectation, result) => {
-    // https://w3c.github.io/webappsec-referrer-policy/#determine-requests-referrer
-    let referrerSource = result.sourceContextUrl;
-    const sentFromSrcdoc = scenario.source_context_list.length > 0 &&
-        scenario.source_context_list[scenario.source_context_list.length - 1]
-        .sourceContextType === 'srcdoc';
-    if (sentFromSrcdoc) {
-      // Step 3. While document is an iframe srcdoc document, let document be
-      // document's browsing context's browsing context container's node
-      // document. [spec text]
-
-      // Workaround for srcdoc cases. Currently we only test <iframe srcdoc>
-      // inside the top-level Document, so |document| in the spec here is
-      // the top-level Document.
-      // This doesn't work if e.g. we test <iframe srcdoc> inside another
-      // external <iframe>.
-      referrerSource = location.toString();
-    }
-    const expectedReferrerUrl =
-      referrerUrlResolver[expectation](referrerSource);
-
-    // Check the reported URL.
-    assert_equals(result.referrer,
-                  expectedReferrerUrl,
-                  "Reported Referrer URL is '" +
-                  expectation + "'.");
-    assert_equals(result.headers.referer,
-                  expectedReferrerUrl,
-                  "Reported Referrer URL from HTTP header is '" +
-                  expectedReferrerUrl + "'");
-  };
-
   function runTest() {
-    function historyBackPromise(t, scenario) {
-      history.back();
-      return new Promise(resolve => {
-          // Wait for completion of `history.back()` by listening the
-          // popstate events that are fired near the end of
-          // `history.back()` processing.
-          window.addEventListener('popstate', resolve, {once: true});
-
-          // Workaround for Safari: Waiting for popstate events causes
-          // timeout in a-tag tests. To avoid timeout, we anyway resolve
-          // the promise.
-          if (scenario.subresource === 'a-tag') {
-            t.step_timeout(resolve, 1000);
-          }
-        });
-    }
-
     promise_test(_ => {
       return invokeScenario(scenario)
-        .then(result => checkResult(scenario.expectation, result));
+        .then(result => checkResult(scenario, scenario.expectation, result));
     }, testDescription);
-
-    // `Referer` headers with length over 4k are culled down to an origin, so,
-    // let's test around that boundary for tests that would otherwise return
-    // the complete URL.
-    // The following tests run only on top-level Documents, because they rely
-    // on navigations using `history`.
-    // Different subresource URLs are used because getRequestURLs() is called
-    // for each sub test which returns a unique URL.
-    if (scenario.expectation == "stripped-referrer" &&
-        scenario.source_context_list.length == 0) {
-      promise_test(t => {
-        history.pushState(null, null, "/");
-        history.replaceState(null, null, "A".repeat(4096 - location.href.length - 1));
-        return invokeScenario(scenario)
-          .then(result => checkResult(scenario.expectation, result))
-          .finally(_ => historyBackPromise(t, scenario));
-      }, "`Referer` header with length < 4k is not stripped to an origin.");
-
-      promise_test(t => {
-        history.pushState(null, null, "/");
-        history.replaceState(null, null, "A".repeat(4096 - location.href.length));
-        return invokeScenario(scenario)
-          .then(result => checkResult(scenario.expectation, result))
-          .finally(_ => historyBackPromise(t, scenario));
-      }, "`Referer` header with length == 4k is not stripped to an origin.");
-
-      promise_test(t => {
-        history.pushState(null, null, "/");
-        history.replaceState(null, null, "A".repeat(4096 - location.href.length + 1));
-        return invokeScenario(scenario)
-          .then(result => checkResult("origin", result))
-          .finally(_ => historyBackPromise(t, scenario));
-      }, "`Referer` header with length > 4k is stripped to an origin.");
-    }
   }
 
   return {start: runTest};
diff --git a/tests/wpt/web-platform-tests/service-workers/service-worker/resources/interfaces-worker.sub.js b/tests/wpt/web-platform-tests/service-workers/service-worker/resources/interfaces-worker.sub.js
index ac79ddc0056..44bd0870b95 100644
--- a/tests/wpt/web-platform-tests/service-workers/service-worker/resources/interfaces-worker.sub.js
+++ b/tests/wpt/web-platform-tests/service-workers/service-worker/resources/interfaces-worker.sub.js
@@ -51,13 +51,13 @@ test(function() {
     assert_equals(
       new ExtendableEvent('ExtendableEvent').type,
       'ExtendableEvent', 'Type of ExtendableEvent should be ExtendableEvent');
-    assert_throws(new TypeError, function() {
+    assert_throws_js(TypeError, function() {
         new FetchEvent('FetchEvent');
     }, 'FetchEvent constructor with one argument throws');
-    assert_throws(new TypeError, function() {
+    assert_throws_js(TypeError, function() {
         new FetchEvent('FetchEvent', {});
     }, 'FetchEvent constructor with empty init dict throws');
-    assert_throws(new TypeError, function() {
+    assert_throws_js(TypeError, function() {
         new FetchEvent('FetchEvent', {request: null});
     }, 'FetchEvent constructor with null request member throws');
     assert_equals(
diff --git a/tests/wpt/web-platform-tests/tools/wptrunner/requirements.txt b/tests/wpt/web-platform-tests/tools/wptrunner/requirements.txt
index 328b43a0737..ccf55d2ca7f 100644
--- a/tests/wpt/web-platform-tests/tools/wptrunner/requirements.txt
+++ b/tests/wpt/web-platform-tests/tools/wptrunner/requirements.txt
@@ -4,6 +4,6 @@ mozlog==5.0
 mozdebug==0.1.1
 # Pillow 7 requires Python 3
 pillow==6.2.1  # pyup: <7.0
-urllib3[secure]==1.25.7
+urllib3[secure]==1.25.8
 requests==2.22.0
 six==1.14.0
diff --git a/tests/wpt/web-platform-tests/tools/wptrunner/wptrunner/executors/base.py b/tests/wpt/web-platform-tests/tools/wptrunner/wptrunner/executors/base.py
index 3d8af4de486..603c606e1cd 100644
--- a/tests/wpt/web-platform-tests/tools/wptrunner/wptrunner/executors/base.py
+++ b/tests/wpt/web-platform-tests/tools/wptrunner/wptrunner/executors/base.py
@@ -1,6 +1,5 @@
 import base64
 import hashlib
-from six.moves.http_client import HTTPConnection
 import io
 import json
 import os
@@ -8,8 +7,10 @@ import threading
 import traceback
 import socket
 import sys
-from six.moves.urllib.parse import urljoin, urlsplit, urlunsplit
 from abc import ABCMeta, abstractmethod
+from six import text_type
+from six.moves.http_client import HTTPConnection
+from six.moves.urllib.parse import urljoin, urlsplit, urlunsplit
 
 from ..testrunner import Stop
 from .protocol import Protocol, BaseProtocolPart
@@ -293,7 +294,7 @@ class TestExecutor(object):
             status = e.status
         else:
             status = "INTERNAL-ERROR"
-        message = unicode(getattr(e, "message", ""))
+        message = text_type(getattr(e, "message", ""))
         if message:
             message += "\n"
         message += traceback.format_exc(e)
diff --git a/tests/wpt/web-platform-tests/tools/wptrunner/wptrunner/manifestexpected.py b/tests/wpt/web-platform-tests/tools/wptrunner/wptrunner/manifestexpected.py
index 65b53f0ab97..335b0da5c90 100644
--- a/tests/wpt/web-platform-tests/tools/wptrunner/wptrunner/manifestexpected.py
+++ b/tests/wpt/web-platform-tests/tools/wptrunner/wptrunner/manifestexpected.py
@@ -1,7 +1,8 @@
 import os
-from six.moves.urllib.parse import urljoin
 from collections import deque
-from six import text_type
+from six import string_types, text_type
+from six.moves.urllib.parse import urljoin
+
 
 from .wptmanifest.backends import static
 from .wptmanifest.backends.base import ManifestItem
@@ -47,7 +48,7 @@ def list_prop(name, node):
     """List property"""
     try:
         list_prop = node.get(name)
-        if isinstance(list_prop, basestring):
+        if isinstance(list_prop, string_types):
             return [list_prop]
         return list(list_prop)
     except KeyError:
diff --git a/tests/wpt/web-platform-tests/tools/wptrunner/wptrunner/process.py b/tests/wpt/web-platform-tests/tools/wptrunner/wptrunner/process.py
index 26e11ddfc87..8a2b894cb74 100644
--- a/tests/wpt/web-platform-tests/tools/wptrunner/wptrunner/process.py
+++ b/tests/wpt/web-platform-tests/tools/wptrunner/wptrunner/process.py
@@ -7,5 +7,5 @@ def cast_env(env):
     """Encode all the environment values as the appropriate type for each Python version
     This assumes that all the data is or can be represented as UTF8"""
 
-    env_type = six.ensure_binary if sys.version_info[0] < 3 else six.ensure_string
+    env_type = six.ensure_binary if sys.version_info[0] < 3 else six.ensure_str
     return {env_type(key): env_type(value) for key, value in six.iteritems(env)}
diff --git a/tests/wpt/web-platform-tests/tools/wptserve/wptserve/handlers.py b/tests/wpt/web-platform-tests/tools/wptserve/wptserve/handlers.py
index efc1a16a932..c18fa2d3792 100644
--- a/tests/wpt/web-platform-tests/tools/wptserve/wptserve/handlers.py
+++ b/tests/wpt/web-platform-tests/tools/wptserve/wptserve/handlers.py
@@ -95,15 +95,29 @@ class DirectoryHandler(object):
             link = urljoin(base_path, "..")
             yield ("""<li class="dir"><a href="%(link)s">%(name)s</a></li>""" %
                    {"link": link, "name": ".."})
+        items = []
+        prev_item = None
         for item in sorted(os.listdir(path)):
+            if prev_item and prev_item + ".headers" == item:
+                items[-1][1] = item
+                prev_item = None
+                continue
+            items.append([item, None])
+            prev_item = item
+        for item, dot_headers in items:
             link = html.escape(quote(item))
+            dot_headers_markup = ""
+            if dot_headers is not None:
+                dot_headers_markup = (""" (<a href="%(link)s">.headers</a>)""" %
+                                      {"link": html.escape(quote(dot_headers))})
             if os.path.isdir(os.path.join(path, item)):
                 link += "/"
                 class_ = "dir"
             else:
                 class_ = "file"
-            yield ("""<li class="%(class)s"><a href="%(link)s">%(name)s</a></li>""" %
-                   {"link": link, "name": html.escape(item), "class": class_})
+            yield ("""<li class="%(class)s"><a href="%(link)s">%(name)s</a>%(headers)s</li>""" %
+                   {"link": link, "name": html.escape(item), "class": class_,
+                    "headers": dot_headers_markup})
 
 
 def wrap_pipeline(path, request, response):
diff --git a/tests/wpt/web-platform-tests/tools/wptserve/wptserve/pipes.py b/tests/wpt/web-platform-tests/tools/wptserve/wptserve/pipes.py
index e5d6e1c96db..3500948fc8c 100644
--- a/tests/wpt/web-platform-tests/tools/wptserve/wptserve/pipes.py
+++ b/tests/wpt/web-platform-tests/tools/wptserve/wptserve/pipes.py
@@ -396,8 +396,8 @@ class SubFunctions(object):
     def uuid(request):
         return str(uuid.uuid4())
 
-    # Maintain a whitelist of supported algorithms, restricted to those that
-    # are available on all platforms [1]. This ensures that test authors do not
+    # Maintain a list of supported algorithms, restricted to those that are
+    # available on all platforms [1]. This ensures that test authors do not
     # unknowingly introduce platform-specific tests.
     #
     # [1] https://docs.python.org/2/library/hashlib.html
diff --git a/tests/wpt/web-platform-tests/trusted-types/TrustedTypePolicy-CSP.tentative.html b/tests/wpt/web-platform-tests/trusted-types/TrustedTypePolicy-CSP.tentative.html
index 0b57c3a908a..8ae162558f4 100644
--- a/tests/wpt/web-platform-tests/trusted-types/TrustedTypePolicy-CSP.tentative.html
+++ b/tests/wpt/web-platform-tests/trusted-types/TrustedTypePolicy-CSP.tentative.html
@@ -6,22 +6,22 @@
 <meta http-equiv="Content-Security-Policy" content="trusted-types SomeName JustOneMoreName">
 <body>
 <script>
-  // Whitelisted name test
+  // Allowed name test
   test(t => {
     let policy = window.trustedTypes.createPolicy('SomeName', { createHTML: s => s } );
     assert_equals(policy.name, 'SomeName');
-  }, "Whitelisted policy creation works.");
+  }, "Allowed-name policy creation works.");
 
-  // Another whitelisted name test
+  // Another allowed name test
   test(t => {
     let policy = window.trustedTypes.createPolicy('JustOneMoreName', { createHTML: s => s } );
     assert_equals(policy.name, 'JustOneMoreName');
-  }, "Another whitelisted policy creation works.");
+  }, "Another allowed-name policy creation works.");
 
-  // Non-whitelisted names test
+  // Non-allowed names test
   test(t => {
     assert_throws(new TypeError(), _ => {
      window.trustedTypes.createPolicy('SomeOtherName', { createURL: s => s } );
     });
-  }, "Non-whitelisted policy creation throws.");
+  }, "Non-allowed name policy creation throws.");
 </script>
diff --git a/tests/wpt/web-platform-tests/trusted-types/TrustedTypePolicyFactory-createPolicy-cspTests.tentative.html b/tests/wpt/web-platform-tests/trusted-types/TrustedTypePolicyFactory-createPolicy-cspTests.tentative.html
index 0b57c3a908a..8ae162558f4 100644
--- a/tests/wpt/web-platform-tests/trusted-types/TrustedTypePolicyFactory-createPolicy-cspTests.tentative.html
+++ b/tests/wpt/web-platform-tests/trusted-types/TrustedTypePolicyFactory-createPolicy-cspTests.tentative.html
@@ -6,22 +6,22 @@
 <meta http-equiv="Content-Security-Policy" content="trusted-types SomeName JustOneMoreName">
 <body>
 <script>
-  // Whitelisted name test
+  // Allowed name test
   test(t => {
     let policy = window.trustedTypes.createPolicy('SomeName', { createHTML: s => s } );
     assert_equals(policy.name, 'SomeName');
-  }, "Whitelisted policy creation works.");
+  }, "Allowed-name policy creation works.");
 
-  // Another whitelisted name test
+  // Another allowed name test
   test(t => {
     let policy = window.trustedTypes.createPolicy('JustOneMoreName', { createHTML: s => s } );
     assert_equals(policy.name, 'JustOneMoreName');
-  }, "Another whitelisted policy creation works.");
+  }, "Another allowed-name policy creation works.");
 
-  // Non-whitelisted names test
+  // Non-allowed names test
   test(t => {
     assert_throws(new TypeError(), _ => {
      window.trustedTypes.createPolicy('SomeOtherName', { createURL: s => s } );
     });
-  }, "Non-whitelisted policy creation throws.");
+  }, "Non-allowed name policy creation throws.");
 </script>
diff --git a/tests/wpt/web-platform-tests/url/failure.html b/tests/wpt/web-platform-tests/url/failure.html
index bebdb3dcc4d..ac16edf8c74 100644
--- a/tests/wpt/web-platform-tests/url/failure.html
+++ b/tests/wpt/web-platform-tests/url/failure.html
@@ -25,7 +25,7 @@ function runTests(testData) {
 
     self.test(() => {
       const url = new URL("about:blank")
-      assert_throws(new TypeError, () => url.href = test.input)
+      assert_throws_js(TypeError, () => url.href = test.input)
     }, "URL's href: " + name)
 
     self.test(() => {
@@ -34,11 +34,11 @@ function runTests(testData) {
     }, "XHR: " + name)
 
     self.test(() => {
-      assert_throws(new TypeError, () => self.navigator.sendBeacon(test.input))
+      assert_throws_js(TypeError, () => self.navigator.sendBeacon(test.input))
     }, "sendBeacon(): " + name)
 
     self.test(() => {
-      assert_throws(new TypeError, () => self[0].location = test.input)
+      assert_throws_js(self[0].TypeError, () => self[0].location = test.input)
     }, "Location's href: " + name)
 
     self.test(() => {
diff --git a/tests/wpt/web-platform-tests/url/toascii.window.js b/tests/wpt/web-platform-tests/url/toascii.window.js
index b28c664479a..cdc488ec285 100644
--- a/tests/wpt/web-platform-tests/url/toascii.window.js
+++ b/tests/wpt/web-platform-tests/url/toascii.window.js
@@ -28,7 +28,7 @@ function runTests(tests) {
           assert_equals(url.href, "https://" + hostTest.output + "/x")
         } else {
           if(type === "url") {
-            assert_throws(new TypeError, () => makeURL("url", hostTest.input))
+            assert_throws_js(TypeError, () => makeURL("url", hostTest.input))
           } else {
             const url = makeURL(type, hostTest.input)
             assert_equals(url.host, "")
diff --git a/tests/wpt/web-platform-tests/wasm/jsapi/table/grow-reftypes.tentative.any.js b/tests/wpt/web-platform-tests/wasm/jsapi/table/grow-reftypes.tentative.any.js
new file mode 100644
index 00000000000..807aea991bb
--- /dev/null
+++ b/tests/wpt/web-platform-tests/wasm/jsapi/table/grow-reftypes.tentative.any.js
@@ -0,0 +1,42 @@
+// META: global=jsshell
+// META: script=assertions.js
+// META: script=/wasm/jsapi/wasm-constants.js
+// META: script=/wasm/jsapi/wasm-module-builder.js
+
+// Test cases for changes to the WebAssembly.Table.prototype.grow() API that
+// come in with the reftypes proposal: the API takes a default argument, which
+// for tables of anyfunc must be either an exported wasm function or null.
+//
+// See:
+//   https://github.com/WebAssembly/reference-types
+//   https://bugzilla.mozilla.org/show_bug.cgi?id=1507491
+//   https://github.com/WebAssembly/reference-types/issues/22
+
+test(() => {
+  const builder = new WasmModuleBuilder();
+  builder
+    .addFunction("fn", kSig_v_v)
+    .addBody([kExprEnd])
+    .exportFunc();
+  const bin = builder.toBuffer()
+  const argument = { "element": "anyfunc", "initial": 1 };
+  const table = new WebAssembly.Table(argument);
+  const fn = new WebAssembly.Instance(new WebAssembly.Module(bin)).exports.fn;
+  const result = table.grow(2, fn);
+  assert_equals(result, 1);
+  assert_equals(table.get(0), null);
+  assert_equals(table.get(1), fn);
+  assert_equals(table.get(2), fn);
+}, "Grow with exported-function argument");
+
+test(() => {
+  const argument = { "element": "anyfunc", "initial": 1 };
+  const table = new WebAssembly.Table(argument);
+  assert_throws(new TypeError(), () => table.grow(2, {}));
+}, "Grow with non-function argument");
+
+test(() => {
+  const argument = { "element": "anyfunc", "initial": 1 };
+  const table = new WebAssembly.Table(argument);
+  assert_throws(new TypeError(), () => table.grow(2, () => true));
+}, "Grow with JS-function argument");
diff --git a/tests/wpt/web-platform-tests/web-animations/interfaces/Animatable/animate.html b/tests/wpt/web-platform-tests/web-animations/interfaces/Animatable/animate.html
index 95d7db7bb3b..4d17d2dd00e 100644
--- a/tests/wpt/web-platform-tests/web-animations/interfaces/Animatable/animate.html
+++ b/tests/wpt/web-platform-tests/web-animations/interfaces/Animatable/animate.html
@@ -81,7 +81,7 @@ for (const subtest of gKeyframesTests) {
 for (const subtest of gInvalidKeyframesTests) {
   test(t => {
     const div = createDiv(t);
-    assert_throws(new TypeError, () => {
+    assert_throws_js(TypeError, () => {
       div.animate(subtest.input, 2000);
     });
   }, `Element.animate() does not accept ${subtest.desc}`);
@@ -108,7 +108,7 @@ test(t => {
 
 for (const invalid of gBadDelayValues) {
   test(t => {
-    assert_throws(new TypeError, () => {
+    assert_throws_js(TypeError, () => {
       createDiv(t).animate(null, { delay: invalid });
     });
   }, `Element.animate() does not accept invalid delay value: ${invalid}`);
@@ -127,7 +127,7 @@ for (const invalid of gBadDurationValues) {
     continue;
   }
   test(t => {
-    assert_throws(new TypeError, () => {
+    assert_throws_js(TypeError, () => {
       createDiv(t).animate(null, invalid);
     });
   }, 'Element.animate() does not accept invalid duration value: '
@@ -136,7 +136,7 @@ for (const invalid of gBadDurationValues) {
 
 for (const invalid of gBadDurationValues) {
   test(t => {
-    assert_throws(new TypeError, () => {
+    assert_throws_js(TypeError, () => {
       createDiv(t).animate(null, { duration: invalid });
     });
   }, 'Element.animate() does not accept invalid duration value: '
@@ -146,7 +146,7 @@ for (const invalid of gBadDurationValues) {
 
 for (const invalidEasing of gInvalidEasings) {
   test(t => {
-    assert_throws(new TypeError, () => {
+    assert_throws_js(TypeError, () => {
       createDiv(t).animate({ easing: invalidEasing }, 2000);
     });
   }, `Element.animate() does not accept invalid easing: '${invalidEasing}'`);
@@ -154,7 +154,7 @@ for (const invalidEasing of gInvalidEasings) {
 
 for (const invalid of gBadIterationStartValues) {
   test(t => {
-    assert_throws(new TypeError, () => {
+    assert_throws_js(TypeError, () => {
       createDiv(t).animate(null, { iterationStart: invalid });
     });
   }, 'Element.animate() does not accept invalid iterationStart value: ' +
@@ -163,7 +163,7 @@ for (const invalid of gBadIterationStartValues) {
 
 for (const invalid of gBadIterationsValues) {
   test(t => {
-    assert_throws(new TypeError, () => {
+    assert_throws_js(TypeError, () => {
       createDiv(t).animate(null, { iterations: invalid });
     });
   }, 'Element.animate() does not accept invalid iterations value: ' +
diff --git a/tests/wpt/web-platform-tests/web-animations/interfaces/AnimationEffect/updateTiming.html b/tests/wpt/web-platform-tests/web-animations/interfaces/AnimationEffect/updateTiming.html
index 746f0d74f19..f4f672ab1aa 100644
--- a/tests/wpt/web-platform-tests/web-animations/interfaces/AnimationEffect/updateTiming.html
+++ b/tests/wpt/web-platform-tests/web-animations/interfaces/AnimationEffect/updateTiming.html
@@ -258,7 +258,7 @@ for (const duration of gGoodDurationValues) {
 
 for (const invalid of gBadDurationValues) {
   test(t => {
-    assert_throws(new TypeError, () => {
+    assert_throws_js(TypeError, () => {
       createDiv(t).animate(null, { duration: invalid });
     });
   }, 'Throws when setting invalid duration: '
diff --git a/tests/wpt/web-platform-tests/web-animations/interfaces/KeyframeEffect/processing-a-keyframes-argument-002.html b/tests/wpt/web-platform-tests/web-animations/interfaces/KeyframeEffect/processing-a-keyframes-argument-002.html
index 8233dc07c5d..e78e13d69aa 100644
--- a/tests/wpt/web-platform-tests/web-animations/interfaces/KeyframeEffect/processing-a-keyframes-argument-002.html
+++ b/tests/wpt/web-platform-tests/web-animations/interfaces/KeyframeEffect/processing-a-keyframes-argument-002.html
@@ -37,7 +37,7 @@ test(() => {
 
 test(() => {
   for (const invalidEasing of gInvalidEasings) {
-    assert_throws(new TypeError, () => {
+    assert_throws_js(TypeError, () => {
       new KeyframeEffect(target, { easing: invalidEasing });
     }, `TypeError is thrown for easing '${invalidEasing}'`);
   }
@@ -46,7 +46,7 @@ test(() => {
 
 test(() => {
   for (const invalidEasing of gInvalidEasings) {
-    assert_throws(new TypeError, () => {
+    assert_throws_js(TypeError, () => {
       new KeyframeEffect(target, [{ easing: invalidEasing }]);
     }, `TypeError is thrown for easing '${invalidEasing}'`);
   }
diff --git a/tests/wpt/web-platform-tests/web-animations/interfaces/KeyframeEffect/setKeyframes.html b/tests/wpt/web-platform-tests/web-animations/interfaces/KeyframeEffect/setKeyframes.html
index 675a705891f..a5c81a29bd9 100644
--- a/tests/wpt/web-platform-tests/web-animations/interfaces/KeyframeEffect/setKeyframes.html
+++ b/tests/wpt/web-platform-tests/web-animations/interfaces/KeyframeEffect/setKeyframes.html
@@ -34,7 +34,7 @@ for (const subtest of gKeyframesTests) {
 for (const subtest of gInvalidKeyframesTests) {
   test(t => {
     const effect = new KeyframeEffect(target, {});
-    assert_throws(new TypeError, () => {
+    assert_throws_js(TypeError, () => {
       effect.setKeyframes(subtest.input);
     });
   }, `KeyframeEffect constructor throws with ${subtest.desc}`);
diff --git a/tests/wpt/web-platform-tests/web-nfc/NDEFMessage_constructor.https.html b/tests/wpt/web-platform-tests/web-nfc/NDEFMessage_constructor.https.html
index 4e53828c310..5d6b557e3cc 100644
--- a/tests/wpt/web-platform-tests/web-nfc/NDEFMessage_constructor.https.html
+++ b/tests/wpt/web-platform-tests/web-nfc/NDEFMessage_constructor.https.html
@@ -8,21 +8,21 @@
 
   test(() => {
     assert_equals(NDEFMessage.length, 1);
-    assert_throws(new TypeError, () => new NDEFMessage());
+    assert_throws_js(TypeError, () => new NDEFMessage());
   }, 'NDEFMessage constructor without init dict');
 
   test(() => {
-    assert_throws(new TypeError, () => new NDEFMessage(null),
+    assert_throws_js(TypeError, () => new NDEFMessage(null),
         'NDEFMessageInit#records is a required field.');
   }, 'NDEFMessage constructor with null init dict');
 
   test(() => {
-    assert_throws(new TypeError, () => new NDEFMessage({dummy_key: 'dummy_value'}),
+    assert_throws_js(TypeError, () => new NDEFMessage({dummy_key: 'dummy_value'}),
         'NDEFMessageInit#records is a required field.');
   }, 'NDEFMessage constructor without NDEFMessageInit#records field');
 
   test(() => {
-    assert_throws(new TypeError, () => new NDEFMessage({records: []}),
+    assert_throws_js(TypeError, () => new NDEFMessage({records: []}),
         'NDEFMessageInit#records should not be empty.');
   }, 'NDEFMessage constructor with NDEFMessageInit#records being empty');
 
diff --git a/tests/wpt/web-platform-tests/web-nfc/NDEFReadingEvent_constructor.https.html b/tests/wpt/web-platform-tests/web-nfc/NDEFReadingEvent_constructor.https.html
index 5427b75ae2b..122070f50ed 100644
--- a/tests/wpt/web-platform-tests/web-nfc/NDEFReadingEvent_constructor.https.html
+++ b/tests/wpt/web-platform-tests/web-nfc/NDEFReadingEvent_constructor.https.html
@@ -8,11 +8,11 @@
 
   test(() => {
     assert_equals(NDEFReadingEvent.length, 2);
-    assert_throws(new TypeError, () => new NDEFReadingEvent('message'));
+    assert_throws_js(TypeError, () => new NDEFReadingEvent('message'));
   }, 'NDEFReadingEvent constructor without init dict');
 
   test(() => {
-    assert_throws(new TypeError, () => new NDEFReadingEvent('type',
+    assert_throws_js(TypeError, () => new NDEFReadingEvent('type',
           {serialNumber: '', message: null}),
         'NDEFMessageInit#records is a required field.');
   }, 'NDEFReadingEvent constructor failed to construct its NDEFMessage');
diff --git a/tests/wpt/web-platform-tests/web-nfc/NDEFRecord_constructor.https.html b/tests/wpt/web-platform-tests/web-nfc/NDEFRecord_constructor.https.html
index a2ea09fa681..bf4697f8b17 100644
--- a/tests/wpt/web-platform-tests/web-nfc/NDEFRecord_constructor.https.html
+++ b/tests/wpt/web-platform-tests/web-nfc/NDEFRecord_constructor.https.html
@@ -8,42 +8,42 @@
 
   test(() => {
     assert_equals(NDEFRecord.length, 1);
-    assert_throws(new TypeError, () => new NDEFRecord());
+    assert_throws_js(TypeError, () => new NDEFRecord());
   }, 'NDEFRecord constructor without init dict');
 
   test(() => {
-    assert_throws(new TypeError, () => new NDEFRecord(null),
+    assert_throws_js(TypeError, () => new NDEFRecord(null),
         'NDEFRecordInit#recordType is a required field.');
   }, 'NDEFRecord constructor with null init dict');
 
   test(() => {
-    assert_throws(new TypeError, () => new NDEFRecord({id: test_record_id, data: test_text_data}),
+    assert_throws_js(TypeError, () => new NDEFRecord({id: test_record_id, data: test_text_data}),
         'NDEFRecordInit#recordType is a required field.');
   }, 'NDEFRecord constructor without NDEFRecordInit#recordType field');
 
   test(() => {
-    assert_throws(new TypeError, () => new NDEFRecord(
+    assert_throws_js(TypeError, () => new NDEFRecord(
           createRecord('empty', test_text_data, test_record_id)),
         'id does not apply for empty record type.');
   }, 'NDEFRecord constructor with empty record type and id');
 
   test(() => {
-    assert_throws(new TypeError, () => new NDEFRecord(
+    assert_throws_js(TypeError, () => new NDEFRecord(
           createRecord('empty', test_text_data, test_record_id, 'text/plain')),
         'mediaType does not apply for empty record type.');
-    assert_throws(new TypeError, () => new NDEFRecord(
+    assert_throws_js(TypeError, () => new NDEFRecord(
           createRecord('text', test_text_data, test_record_id, 'text/plain')),
         'mediaType does not apply for text record type.');
-    assert_throws(new TypeError, () => new NDEFRecord(
+    assert_throws_js(TypeError, () => new NDEFRecord(
           createRecord('url', test_url_data, test_record_id, 'text/plain')),
         'mediaType does not apply for url record type.');
-    assert_throws(new TypeError, () => new NDEFRecord(
+    assert_throws_js(TypeError, () => new NDEFRecord(
           createRecord('absolute-url', test_url_data, test_record_id, 'text/plain')),
         'mediaType does not apply for absolute-url record type.');
-    assert_throws(new TypeError, () => new NDEFRecord(
+    assert_throws_js(TypeError, () => new NDEFRecord(
           createRecord('unknown', test_buffer_data, test_record_id, 'application/octet-stream')),
         'mediaType does not apply for unknown record type.');
-    assert_throws(new TypeError, () => new NDEFRecord(
+    assert_throws_js(TypeError, () => new NDEFRecord(
           createRecord('foo.example.com:bar', test_buffer_data, test_record_id, 'application/octet-stream')),
         'mediaType does not apply for external record type.');
   }, 'NDEFRecord constructor should only accept mediaType for mime record type');
@@ -207,7 +207,7 @@
   }, 'NDEFRecord constructor with absolute-url record type');
 
   test(() => {
-    assert_throws(new TypeError, () => new NDEFRecord(
+    assert_throws_js(TypeError, () => new NDEFRecord(
           createMimeRecord("A string is not a BufferSource")),
         'Only BufferSource is allowed to be the record data.');
 
@@ -250,7 +250,7 @@
   }, 'NDEFRecord constructor with mime record type and json data');
 
   test(() => {
-    assert_throws(new TypeError, () => new NDEFRecord(
+    assert_throws_js(TypeError, () => new NDEFRecord(
           createUnknownRecord("A string is not a BufferSource")),
         'Only BufferSource is allowed to be the record data.');
 
@@ -280,7 +280,7 @@
   }, 'NDEFRecord constructor with unknown record type');
 
   test(() => {
-    assert_throws(new TypeError, () => new NDEFRecord(
+    assert_throws_js(TypeError, () => new NDEFRecord(
         createRecord('foo.eXamPle.com:bAr*-', "A string is not a BufferSource or NDEFMessageInit")),
         'Only BufferSource and NDEFMessageInit are allowed to be the record data.');
 
@@ -331,15 +331,15 @@
   }, 'NDEFRecord constructor with external record type');
 
   test(() => {
-    assert_throws(new TypeError, () => new NDEFRecord(createRecord('EMptY')),
+    assert_throws_js(TypeError, () => new NDEFRecord(createRecord('EMptY')),
         'Unknown record type.');
-    assert_throws(new TypeError, () => new NDEFRecord(createRecord('TeXt', test_text_data)),
+    assert_throws_js(TypeError, () => new NDEFRecord(createRecord('TeXt', test_text_data)),
         'Unknown record type.');
-    assert_throws(new TypeError, () => new NDEFRecord(createRecord('uRL', test_url_data)),
+    assert_throws_js(TypeError, () => new NDEFRecord(createRecord('uRL', test_url_data)),
         'Unknown record type.');
-    assert_throws(new TypeError, () => new NDEFRecord(createRecord('Mime', test_buffer_data)),
+    assert_throws_js(TypeError, () => new NDEFRecord(createRecord('Mime', test_buffer_data)),
         'Unknown record type.');
-    assert_throws(new TypeError, () => new NDEFRecord(createRecord('sMart-PosTER', test_url_data)),
+    assert_throws_js(TypeError, () => new NDEFRecord(createRecord('sMart-PosTER', test_url_data)),
         'Unknown record type.');
   }, 'NDEFRecord constructor with record type string being treated as case sensitive');
 
@@ -352,21 +352,21 @@
     const record = new NDEFRecord(createRecord(
         [...Array(251)].map(_ => 'a').join('') + ':xyz', test_buffer_data));
     // Exceeding 255, Throws.
-    assert_throws(new TypeError, () => new NDEFRecord(createRecord(
+    assert_throws_js(TypeError, () => new NDEFRecord(createRecord(
         [...Array(252)].map(_ => 'a').join('') + ':xyz', test_buffer_data)),
         'The external type should not be longer than 255.');
 
-    assert_throws(new TypeError, () => new NDEFRecord(createRecord(
+    assert_throws_js(TypeError, () => new NDEFRecord(createRecord(
         'xyz', test_buffer_data)), 'The external type must have a \':\'.');
-    assert_throws(new TypeError, () => new NDEFRecord(createRecord(
+    assert_throws_js(TypeError, () => new NDEFRecord(createRecord(
         ':xyz', test_buffer_data)), 'The domain should not be empty.');
-    assert_throws(new TypeError, () => new NDEFRecord(createRecord(
+    assert_throws_js(TypeError, () => new NDEFRecord(createRecord(
         'example.com:', test_buffer_data)), 'The type should not be empty.');
-    assert_throws(new TypeError, () => new NDEFRecord(createRecord(
+    assert_throws_js(TypeError, () => new NDEFRecord(createRecord(
         'example.com:xyz[', test_buffer_data)), 'The type should not contain \'[\'.');
-    assert_throws(new TypeError, () => new NDEFRecord(createRecord(
+    assert_throws_js(TypeError, () => new NDEFRecord(createRecord(
         'example.com:xyz~', test_buffer_data)), 'The type should not contain \'~\'.');
-    assert_throws(new TypeError, () => new NDEFRecord(createRecord(
+    assert_throws_js(TypeError, () => new NDEFRecord(createRecord(
         'example.com:xyz/', test_buffer_data)), 'The type should not contain \'/\'.');
   }, 'NDEFRecord constructor with invalid external record type');
 
diff --git a/tests/wpt/web-platform-tests/webmessaging/with-options/null-transfer.html b/tests/wpt/web-platform-tests/webmessaging/with-options/null-transfer.html
index 72bebd1e38e..2ea09eb7ab4 100644
--- a/tests/wpt/web-platform-tests/webmessaging/with-options/null-transfer.html
+++ b/tests/wpt/web-platform-tests/webmessaging/with-options/null-transfer.html
@@ -5,6 +5,6 @@
 <div id=log></div>
 <script>
 test(function(t) {
-  assert_throws(new TypeError, () => postMessage('', {transfer: null}));
+  assert_throws_js(TypeError, () => postMessage('', {transfer: null}));
 });
 </script>
diff --git a/tests/wpt/web-platform-tests/webmessaging/with-ports/023.html b/tests/wpt/web-platform-tests/webmessaging/with-ports/023.html
index da6a5c49a44..e2569a8463f 100644
--- a/tests/wpt/web-platform-tests/webmessaging/with-ports/023.html
+++ b/tests/wpt/web-platform-tests/webmessaging/with-ports/023.html
@@ -5,7 +5,7 @@
 <div id=log></div>
 <script>
 test(function(t) {
-  assert_throws(new TypeError, () => postMessage('', '*', null));
+  assert_throws_js(TypeError, () => postMessage('', '*', null));
 });
 </script>
 
diff --git a/tests/wpt/web-platform-tests/webrtc-extensions/RTCRtpParameters-maxFramerate.html b/tests/wpt/web-platform-tests/webrtc-extensions/RTCRtpParameters-maxFramerate.html
new file mode 100644
index 00000000000..7067fbc7998
--- /dev/null
+++ b/tests/wpt/web-platform-tests/webrtc-extensions/RTCRtpParameters-maxFramerate.html
@@ -0,0 +1,39 @@
+<!doctype html>
+<meta charset=utf-8>
+<title>RTCRtpParameters encodings</title>
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<script src="/webrtc/dictionary-helper.js"></script>
+<script src="/webrtc/RTCRtpParameters-helper.js"></script>
+<script>
+'use strict';
+
+test(function(t) {
+  const pc = new RTCPeerConnection();
+  t.add_cleanup(() => pc.close());
+  assert_throws(new RangeError(), () => pc.addTransceiver('video', {
+    sendEncodings: [{
+      maxFramerate: -10
+    }]
+  }));
+}, `addTransceiver() with sendEncoding.maxFramerate field set to less than 0 should reject with RangeError`);
+
+promise_test(async t => {
+  const pc = new RTCPeerConnection();
+  t.add_cleanup(() => pc.close());
+  const { sender } = pc.addTransceiver('video');
+  await doOfferAnswerExchange(t, pc);
+
+  const param = sender.getParameters();
+  validateSenderRtpParameters(param);
+  const encoding = getFirstEncoding(param);
+
+  encoding.maxFramerate = -10;
+  return promise_rejects(t, new RangeError(),
+    sender.setParameters(param));
+}, `setParameters() with encoding.maxFramerate field set to less than 0 should reject with RangeError`);
+
+test_modified_encoding('video', 'maxFramerate', 24, 16,
+  'setParameters() with modified encoding.maxFramerate should succeed');
+
+</script>
diff --git a/tests/wpt/web-platform-tests/webrtc-identity/RTCPeerConnection-constructor.html b/tests/wpt/web-platform-tests/webrtc-identity/RTCPeerConnection-constructor.html
index 8498e6b35c9..e7b7016338d 100644
--- a/tests/wpt/web-platform-tests/webrtc-identity/RTCPeerConnection-constructor.html
+++ b/tests/wpt/web-platform-tests/webrtc-identity/RTCPeerConnection-constructor.html
@@ -6,6 +6,6 @@
 <script>
 test(() => {
     const toStringThrows = { toString: function() { throw new Error; } };
-    assert_throws(new Error, () => new RTCPeerConnection({ peerIdentity: toStringThrows }));
+    assert_throws_js(Error, () => new RTCPeerConnection({ peerIdentity: toStringThrows }));
 }, "RTCPeerConnection constructor throws if the given peerIdentity getter throws");
 </script>
diff --git a/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-createDataChannel.html b/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-createDataChannel.html
index 943e5728775..350f7156782 100644
--- a/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-createDataChannel.html
+++ b/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-createDataChannel.html
@@ -34,7 +34,6 @@ const stopTracks = (...streams) => {
         readonly attribute USVString           protocol;
         readonly attribute boolean             negotiated;
         readonly attribute unsigned short?     id;
-        readonly attribute RTCPriorityType     priority;
         readonly attribute RTCDataChannelState readyState;
         readonly attribute unsigned long       bufferedAmount;
                  attribute unsigned long       bufferedAmountLowThreshold;
@@ -51,16 +50,6 @@ const stopTracks = (...streams) => {
         boolean         negotiated = false;
         [EnforceRange]
         unsigned short  id;
-        RTCPriorityType priority = "low";
-    };
-
-  4.9.1.  RTCPriorityType Enum
-
-    enum RTCPriorityType {
-      "very-low",
-      "low",
-      "medium",
-      "high"
     };
  */
 
@@ -102,8 +91,6 @@ test(t => {
         member.
     15. Let channel have an [[DataChannelId]] internal slot initialized to option's id
         member, if it is present and [[Negotiated]] is true, otherwise null.
-    17. Let channel have an [[DataChannelPriority]] internal slot initialized to option's
-        priority member.
     21. If the [[DataChannelId]] slot is null (due to no ID being passed into
         createDataChannel, or [[Negotiated]] being false), and the DTLS role of the SCTP
         transport has already been negotiated, then initialize [[DataChannelId]] to a value
@@ -148,7 +135,6 @@ test(t => {
   // Since no offer/answer exchange has occurred yet, the DTLS role is unknown
   // and so the ID should be null.
   assert_equals(dc.id, null);
-  assert_equals(dc.priority, 'low');
   assert_equals(dc.readyState, 'connecting');
   assert_equals(dc.bufferedAmount, 0);
   assert_equals(dc.bufferedAmountLowThreshold, 0);
@@ -165,8 +151,7 @@ test(t => {
     // Note: maxPacketLifeTime is not set in this test.
     protocol: 'custom',
     negotiated: true,
-    id: 3,
-    priority: 'high'
+    id: 3
   });
 
   assert_true(dc instanceof RTCDataChannel, 'is RTCDataChannel');
@@ -177,7 +162,6 @@ test(t => {
   assert_equals(dc.protocol, 'custom');
   assert_equals(dc.negotiated, true);
   assert_equals(dc.id, 3);
-  assert_equals(dc.priority, 'high');
   assert_equals(dc.readyState, 'connecting');
   assert_equals(dc.bufferedAmount, 0);
   assert_equals(dc.bufferedAmountLowThreshold, 0);
@@ -189,7 +173,7 @@ test(t => {
   });
   assert_equals(dc2.label, 'test2');
   assert_equals(dc2.maxPacketLifeTime, 42);
-  assert_equals(dc.maxRetransmits, null);
+  assert_equals(dc2.maxRetransmits, null);
 }, 'createDataChannel with provided parameters should initialize attributes to provided values');
 
 /*
@@ -367,28 +351,6 @@ for (const id of [-1, 65535, 65536]) {
   }, `createDataChannel with id ${id} should throw TypeError`);
 }
 
-/*
-  6.2.  RTCDataChannel
-    createDataChannel
-      17. Let channel have an [[DataChannelPriority]] internal slot initialized to option's
-          priority member.
- */
-test(t => {
-  const pc = new RTCPeerConnection();
-  t.add_cleanup(() => pc.close());
-
-  const dc = pc.createDataChannel('', { priority: 'high' });
-  assert_equals(dc.priority, 'high');
-}, 'createDataChannel with priority "high" should succeed');
-
-test(t => {
-  const pc = new RTCPeerConnection();
-  t.add_cleanup(() => pc.close());
-
-  assert_throws(new TypeError(),
-    () => pc.createDataChannel('', { priority: 'invalid' }));
-}, 'createDataChannel with invalid priority should throw TypeError');
-
 /*
   6.2.  createDataChannel
     5.  If [[DataChannelLabel]] is longer than 65535 bytes, throw a TypeError.
diff --git a/tests/wpt/web-platform-tests/webrtc/RTCRtpParameters-encodings.html b/tests/wpt/web-platform-tests/webrtc/RTCRtpParameters-encodings.html
index c9e14cb374b..f71964429ae 100644
--- a/tests/wpt/web-platform-tests/webrtc/RTCRtpParameters-encodings.html
+++ b/tests/wpt/web-platform-tests/webrtc/RTCRtpParameters-encodings.html
@@ -49,7 +49,6 @@
         RTCPriorityType     priority;
         RTCPriorityType     networkPriority;
         unsigned long       maxBitrate;
-        double              maxFramerate;
 
         [readonly]
         DOMString           rid;
@@ -68,14 +67,6 @@
         - encodings is set to the value of the [[send encodings]] internal slot.
    */
 
-  // Get the first encoding in param.encodings.
-  // Asserts that param.encodings has at least one element.
-  function getFirstEncoding(param) {
-    const { encodings } = param;
-    assert_equals(encodings.length, 1);
-    return encodings[0];
-  }
-
   /*
     5.1.  addTransceiver
       7. Create an RTCRtpSender with track, streams and sendEncodings and let sender
@@ -155,7 +146,6 @@
     assert_equals(encoding.priority, 'low');
     assert_equals(encoding.networkPriority, 'low');
     assert_equals(encoding.maxBitrate, 8);
-    assert_equals(encoding.maxFramerate, 25);
     assert_not_own_property(encoding, "rid", "rid should be removed with a single encoding");
 
   }, `sender.getParameters() should return sendEncodings set by addTransceiver()`);
@@ -267,58 +257,6 @@
     });
   }, `setParameters() with encoding.scaleResolutionDownBy field set to greater than 1.0 should succeed`);
 
-  // Helper function to test that modifying an encoding field should succeed
-  function test_modified_encoding(kind, field, value1, value2, desc) {
-    promise_test(async t => {
-      const pc = new RTCPeerConnection();
-      t.add_cleanup(() => pc.close());
-      const { sender } = pc.addTransceiver(kind, {
-        sendEncodings: [{
-          [field]: value1
-        }]
-      });
-      await doOfferAnswerExchange(t, pc);
-
-      const param1 = sender.getParameters();
-      validateSenderRtpParameters(param1);
-      const encoding1 = getFirstEncoding(param1);
-
-      assert_equals(encoding1[field], value1);
-      encoding1[field] = value2;
-
-      await sender.setParameters(param1);
-      const param2 = sender.getParameters();
-      validateSenderRtpParameters(param2);
-      const encoding2 = getFirstEncoding(param2);
-      assert_equals(encoding2[field], value2);
-    }, desc + ' with RTCRtpTransceiverInit');
-
-    promise_test(async t => {
-      const pc = new RTCPeerConnection();
-      t.add_cleanup(() => pc.close());
-      const { sender } = pc.addTransceiver(kind);
-      await doOfferAnswerExchange(t, pc);
-
-      const initParam = sender.getParameters();
-      validateSenderRtpParameters(initParam);
-      initParam.encodings[0][field] = value1;
-      await sender.setParameters(initParam);
-
-      const param1 = sender.getParameters();
-      validateSenderRtpParameters(param1);
-      const encoding1 = getFirstEncoding(param1);
-
-      assert_equals(encoding1[field], value1);
-      encoding1[field] = value2;
-
-      await sender.setParameters(param1);
-      const param2 = sender.getParameters();
-      validateSenderRtpParameters(param2);
-      const encoding2 = getFirstEncoding(param2);
-      assert_equals(encoding2[field], value2);
-    }, desc + ' without RTCRtpTransceiverInit');
-  }
-
   test_modified_encoding('audio', 'active', false, true,
     'setParameters() with modified encoding.active should succeed');
 
@@ -331,9 +269,6 @@
   test_modified_encoding('audio', 'maxBitrate', 10000, 20000,
     'setParameters() with modified encoding.maxBitrate should succeed');
 
-  test_modified_encoding('video', 'maxFramerate', 24, 16,
-    'setParameters() with modified encoding.maxFramerate should succeed');
-
   test_modified_encoding('video', 'scaleResolutionDownBy', 2, 4,
     'setParameters() with modified encoding.scaleResolutionDownBy should succeed');
 
diff --git a/tests/wpt/web-platform-tests/webrtc/RTCRtpParameters-helper.js b/tests/wpt/web-platform-tests/webrtc/RTCRtpParameters-helper.js
index d7069493008..d61d8e14932 100644
--- a/tests/wpt/web-platform-tests/webrtc/RTCRtpParameters-helper.js
+++ b/tests/wpt/web-platform-tests/webrtc/RTCRtpParameters-helper.js
@@ -242,3 +242,69 @@ function validateCodecParameters(codec) {
   assert_optional_unsigned_int_field(codec, 'channels');
   assert_optional_string_field(codec, 'sdpFmtpLine');
 }
+
+// Get the first encoding in param.encodings.
+// Asserts that param.encodings has at least one element.
+function getFirstEncoding(param) {
+  const {
+    encodings
+  } = param;
+  assert_equals(encodings.length, 1);
+  return encodings[0];
+}
+
+// Helper function to test that modifying an encoding field should succeed
+function test_modified_encoding(kind, field, value1, value2, desc) {
+  promise_test(async t => {
+    const pc = new RTCPeerConnection();
+    t.add_cleanup(() => pc.close());
+    const {
+      sender
+    } = pc.addTransceiver(kind, {
+      sendEncodings: [{
+        [field]: value1
+      }]
+    });
+    await doOfferAnswerExchange(t, pc);
+
+    const param1 = sender.getParameters();
+    validateSenderRtpParameters(param1);
+    const encoding1 = getFirstEncoding(param1);
+
+    assert_equals(encoding1[field], value1);
+    encoding1[field] = value2;
+
+    await sender.setParameters(param1);
+    const param2 = sender.getParameters();
+    validateSenderRtpParameters(param2);
+    const encoding2 = getFirstEncoding(param2);
+    assert_equals(encoding2[field], value2);
+  }, desc + ' with RTCRtpTransceiverInit');
+
+  promise_test(async t => {
+    const pc = new RTCPeerConnection();
+    t.add_cleanup(() => pc.close());
+    const {
+      sender
+    } = pc.addTransceiver(kind);
+    await doOfferAnswerExchange(t, pc);
+
+    const initParam = sender.getParameters();
+    validateSenderRtpParameters(initParam);
+    initParam.encodings[0][field] = value1;
+    await sender.setParameters(initParam);
+
+    const param1 = sender.getParameters();
+    validateSenderRtpParameters(param1);
+    const encoding1 = getFirstEncoding(param1);
+
+    assert_equals(encoding1[field], value1);
+    encoding1[field] = value2;
+
+    await sender.setParameters(param1);
+    const param2 = sender.getParameters();
+    validateSenderRtpParameters(param2);
+    const encoding2 = getFirstEncoding(param2);
+    assert_equals(encoding2[field], value2);
+  }, desc + ' without RTCRtpTransceiverInit');
+}
\ No newline at end of file
diff --git a/tests/wpt/web-platform-tests/webstorage/event_constructor.html b/tests/wpt/web-platform-tests/webstorage/event_constructor.html
index fe7fca77a93..e0bb3f374f4 100644
--- a/tests/wpt/web-platform-tests/webstorage/event_constructor.html
+++ b/tests/wpt/web-platform-tests/webstorage/event_constructor.html
@@ -8,7 +8,7 @@
  <body>
     <script>
         test(function() {
-            assert_throws(new TypeError, () => new StorageEvent());
+            assert_throws_js(TypeError, () => new StorageEvent());
             // should be redundant, but .length can be wrong with custom bindings
             assert_equals(StorageEvent.length, 1, 'StorageEvent.length');
         }, 'constructor with no arguments');
diff --git a/tests/wpt/web-platform-tests/webstorage/event_initstorageevent.html b/tests/wpt/web-platform-tests/webstorage/event_initstorageevent.html
index 2fe89314361..b06a01617a8 100644
--- a/tests/wpt/web-platform-tests/webstorage/event_initstorageevent.html
+++ b/tests/wpt/web-platform-tests/webstorage/event_initstorageevent.html
@@ -9,7 +9,7 @@
     <script>
         test(() => {
             const event = new StorageEvent('storage');
-            assert_throws(new TypeError, () => event.initStorageEvent());
+            assert_throws_js(TypeError, () => event.initStorageEvent());
             // should be redundant, but .length can be wrong with custom bindings
             assert_equals(event.initStorageEvent.length, 1, 'event.initStorageEvent.length');
         }, 'initStorageEvent with 0 arguments');
diff --git a/tests/wpt/web-platform-tests/webvtt/api/VTTCue/constructor-exceptions.html b/tests/wpt/web-platform-tests/webvtt/api/VTTCue/constructor-exceptions.html
index 4d051fb3e98..843cab09845 100644
--- a/tests/wpt/web-platform-tests/webvtt/api/VTTCue/constructor-exceptions.html
+++ b/tests/wpt/web-platform-tests/webvtt/api/VTTCue/constructor-exceptions.html
@@ -5,14 +5,14 @@
 <div id=log></div>
 <script>
 test(function() {
-    assert_throws(new TypeError, function() { new VTTCue(NaN, 0, 'foo'); });
-    assert_throws(new TypeError, function() { new VTTCue(Infinity, 0, 'foo'); });
-    assert_throws(new TypeError, function() { new VTTCue('tomorrow', 0, 'foo'); });
+    assert_throws_js(TypeError, function() { new VTTCue(NaN, 0, 'foo'); });
+    assert_throws_js(TypeError, function() { new VTTCue(Infinity, 0, 'foo'); });
+    assert_throws_js(TypeError, function() { new VTTCue('tomorrow', 0, 'foo'); });
 }, document.title+', non-finite start time');
 test(function() {
-    assert_throws(new TypeError, function() { new VTTCue(0, NaN, 'foo'); });
-    assert_throws(new TypeError, function() { new VTTCue(0, Infinity, 'foo'); });
-    assert_throws(new TypeError, function() { new VTTCue(0, 'tomorrow', 'foo'); });
+    assert_throws_js(TypeError, function() { new VTTCue(0, NaN, 'foo'); });
+    assert_throws_js(TypeError, function() { new VTTCue(0, Infinity, 'foo'); });
+    assert_throws_js(TypeError, function() { new VTTCue(0, 'tomorrow', 'foo'); });
 }, document.title+', non-finite end time');
 test(function() {
     var start = { valueOf: function() { return 42; } };
diff --git a/tests/wpt/web-platform-tests/workers/modules/dedicated-worker-import-blob-url.any.js b/tests/wpt/web-platform-tests/workers/modules/dedicated-worker-import-blob-url.any.js
index f51a821d181..e5d79add736 100644
--- a/tests/wpt/web-platform-tests/workers/modules/dedicated-worker-import-blob-url.any.js
+++ b/tests/wpt/web-platform-tests/workers/modules/dedicated-worker-import-blob-url.any.js
@@ -13,7 +13,11 @@ function import_blob_url_test(testCase) {
     worker.postMessage('Send message for tests from main script.');
     const msgEvent = await new Promise((resolve, reject) => {
       worker.onmessage = resolve;
-      worker.onerror = (error) => reject(error && error.message);
+      worker.onerror = error => {
+        const msg = error instanceof ErrorEvent ? error.message
+                                                : 'unknown error';
+        reject(msg);
+      };
     });
     assert_array_equals(msgEvent.data, testCase.expectation);
   }, testCase.description);
diff --git a/tests/wpt/web-platform-tests/workers/modules/dedicated-worker-import-failure.html b/tests/wpt/web-platform-tests/workers/modules/dedicated-worker-import-failure.html
index 439bea888b2..5e8b152195a 100644
--- a/tests/wpt/web-platform-tests/workers/modules/dedicated-worker-import-failure.html
+++ b/tests/wpt/web-platform-tests/workers/modules/dedicated-worker-import-failure.html
@@ -38,7 +38,11 @@ promise_test(async () => {
   worker.postMessage(scriptURL);
   const msg_event = await new Promise((resolve, reject) => {
     worker.onmessage = resolve;
-    worker.onerror = (error) => reject(error && error.message);
+    worker.onerror = error => {
+      const msg = error instanceof ErrorEvent ? error.message
+                                              : 'unknown error';
+      reject(msg);
+    };
   });
   assert_equals(msg_event.data, 'TypeError');
 }, 'Dynamic import for non-existent script should throw an exception.');
diff --git a/tests/wpt/web-platform-tests/workers/modules/dedicated-worker-import-meta.html b/tests/wpt/web-platform-tests/workers/modules/dedicated-worker-import-meta.html
index 9292b0f6d8e..4ed56e279f7 100644
--- a/tests/wpt/web-platform-tests/workers/modules/dedicated-worker-import-meta.html
+++ b/tests/wpt/web-platform-tests/workers/modules/dedicated-worker-import-meta.html
@@ -9,7 +9,11 @@ promise_test(() => {
   const worker = new Worker(script_url, { type: 'module' });
   return new Promise((resolve, reject) => {
         worker.onmessage = resolve;
-        worker.onerror = (error) => reject(error && error.message);
+        worker.onerror = error => {
+          const msg = error instanceof ErrorEvent ? error.message
+                                                  : 'unknown error';
+          reject(msg);
+        };
       })
       .then(msg_event => assert_true(msg_event.data.endsWith(script_url)));
 }, 'Test import.meta.url on the top-level module script.');
@@ -21,7 +25,11 @@ promise_test(() => {
   worker.postMessage('./' + script_url);
   return new Promise((resolve, reject) => {
         worker.onmessage = resolve;
-        worker.onerror = (error) => reject(error && error.message);
+        worker.onerror = error => {
+          const msg = error instanceof ErrorEvent ? error.message
+                                                  : 'unknown error';
+          reject(msg);
+        };
       })
       .then(msg_event => assert_true(msg_event.data.endsWith(script_url)));
 }, 'Test import.meta.url on the imported module script.');
@@ -34,7 +42,11 @@ promise_test(() => {
 
   return new Promise((resolve, reject) => {
         worker.onmessage = resolve;
-        worker.onerror = (error) => reject(error && error.message);
+        worker.onerror = error => {
+          const msg = error instanceof ErrorEvent ? error.message
+                                                  : 'unknown error';
+          reject(msg);
+        };
       })
       .then(msg_event => assert_true(msg_event.data.endsWith(script_url)))
       .then(() => {
diff --git a/tests/wpt/web-platform-tests/workers/modules/dedicated-worker-import.any.js b/tests/wpt/web-platform-tests/workers/modules/dedicated-worker-import.any.js
index 308c5e74c15..d5bb6cccbe2 100644
--- a/tests/wpt/web-platform-tests/workers/modules/dedicated-worker-import.any.js
+++ b/tests/wpt/web-platform-tests/workers/modules/dedicated-worker-import.any.js
@@ -9,7 +9,11 @@ function import_test(testCase) {
     worker.postMessage('Send message for tests from main script.');
     const msgEvent = await new Promise((resolve, reject) => {
       worker.onmessage = resolve;
-      worker.onerror = (error) => reject(error && error.message);
+      worker.onerror = error => {
+        const msg = error instanceof ErrorEvent ? error.message
+                                                : 'unknown error';
+        reject(msg);
+      };
     });
     assert_array_equals(msgEvent.data, testCase.expectation);
   }, testCase.description);
diff --git a/tests/wpt/web-platform-tests/workers/modules/dedicated-worker-options-type.html b/tests/wpt/web-platform-tests/workers/modules/dedicated-worker-options-type.html
index b7c96b15295..74523f4478b 100644
--- a/tests/wpt/web-platform-tests/workers/modules/dedicated-worker-options-type.html
+++ b/tests/wpt/web-platform-tests/workers/modules/dedicated-worker-options-type.html
@@ -25,23 +25,22 @@ promise_test(() => {
 }, 'Test worker construction with the "module" worker type.');
 
 test(() => {
-  try {
-    new Worker('resources/post-message-on-load-worker.js', { type: '' });
-    assert_unreached(
-        'Worker construction with an empty type should throw an exception');
-  } catch (e) {
-    assert_equals(e.name, 'TypeError');
-  }
+  assert_throws(
+      new TypeError(),
+      () => {
+        new Worker('resources/post-message-on-load-worker.js', { type: '' });
+      },
+      'Worker construction with an empty type should throw an exception');
 }, 'Test worker construction with an empty worker type.');
 
 test(() => {
-  try {
-    new Worker('resources/post-message-on-load-worker.js', { type: 'unknown' });
-    assert_unreached(
-        'Worker construction with an unknown type should throw an exception');
-  } catch (e) {
-    assert_equals(e.name, 'TypeError');
-  }
+  assert_throws(
+      new TypeError(),
+      () => {
+        new Worker('resources/post-message-on-load-worker.js',
+                   { type: 'unknown' });
+      },
+      'Worker construction with an unknown type should throw an exception');
 }, 'Test worker construction with an unknown worker type.');
 
 </script>
diff --git a/tests/wpt/web-platform-tests/workers/modules/shared-worker-import-blob-url.any.js b/tests/wpt/web-platform-tests/workers/modules/shared-worker-import-blob-url.any.js
index d9e9e34c394..f56c1a5525f 100644
--- a/tests/wpt/web-platform-tests/workers/modules/shared-worker-import-blob-url.any.js
+++ b/tests/wpt/web-platform-tests/workers/modules/shared-worker-import-blob-url.any.js
@@ -14,7 +14,11 @@ function import_blob_url_test(testCase) {
     worker.port.postMessage('Send message for tests from main script.');
     const msgEvent = await new Promise((resolve, reject) => {
       worker.port.onmessage = resolve;
-      worker.onerror = (error) => reject(error && error.message);
+      worker.onerror = error => {
+        const msg = error instanceof ErrorEvent ? error.message
+                                                : 'unknown error';
+        reject(msg);
+      };
     });
     assert_array_equals(msgEvent.data, testCase.expectation);
   }, testCase.description);
diff --git a/tests/wpt/web-platform-tests/workers/modules/shared-worker-import.any.js b/tests/wpt/web-platform-tests/workers/modules/shared-worker-import.any.js
index 450d4ad422b..15dfdde067a 100644
--- a/tests/wpt/web-platform-tests/workers/modules/shared-worker-import.any.js
+++ b/tests/wpt/web-platform-tests/workers/modules/shared-worker-import.any.js
@@ -10,7 +10,11 @@ function import_test(testCase) {
     worker.port.postMessage('Send message for tests from main script.');
     const msgEvent = await new Promise((resolve, reject) => {
       worker.port.onmessage = resolve;
-      worker.onerror = (error) => reject(error && error.message);
+      worker.onerror = error => {
+        const msg = error instanceof ErrorEvent ? error.message
+                                                : 'unknown error';
+        reject(msg);
+      };
     });
     assert_array_equals(msgEvent.data, testCase.expectation);
   }, testCase.description);