diff --git a/tests/wpt/metadata/MANIFEST.json b/tests/wpt/metadata/MANIFEST.json
index 493a547882e..38ead3071d5 100644
--- a/tests/wpt/metadata/MANIFEST.json
+++ b/tests/wpt/metadata/MANIFEST.json
@@ -230368,23 +230368,6 @@
      }
     }
    },
-   "std-toast": {
-    "ref-tests": {
-     "toast-slotting.html": [
-      "4d6f5038f2d6ffa80ebdfa12798c8c4202b39670",
-      [
-       null,
-       [
-        [
-         "/std-toast/ref-tests/toast-slotting-expected.html",
-         "=="
-        ]
-       ],
-       {}
-      ]
-     ]
-    }
-   },
    "svg": {
     "coordinate-systems": {
      "abspos.html": [
@@ -239750,7 +239733,7 @@
      []
     ],
     "beacon-common.sub.js": [
-     "ae2f169f272e9efbbea3b7464ea77c34fe65c6e1",
+     "3635da73b75400ed3699576e2eac6329c39bba1b",
      []
     ],
     "headers": {
@@ -239761,7 +239744,7 @@
     },
     "resources": {
      "beacon.py": [
-      "5f2553d3c4d506f7e292cfb73d81930a83a12d76",
+      "34b55b1a95b9fb6b925b71541a090f23a4aba21d",
       []
      ],
      "content-type.py": [
@@ -315646,7 +315629,7 @@
        []
       ],
       "postback.html.headers": [
-       "6604450991a122e3e241e40b1b9e0516c525389d",
+       "4e798cd9f5d3f756df077a43ce9a1a6f9b41fd28",
        []
       ]
      }
@@ -319657,7 +319640,7 @@
         []
        ],
        "echo-iframe.html.headers": [
-        "6604450991a122e3e241e40b1b9e0516c525389d",
+        "4e798cd9f5d3f756df077a43ce9a1a6f9b41fd28",
         []
        ],
        "echo-worker.js": [
@@ -341080,24 +341063,6 @@
      []
     ]
    },
-   "std-toast": {
-    "META.yml": [
-     "c54357a03f214572481fc08be473cc308d50097b",
-     []
-    ],
-    "ref-tests": {
-     "toast-slotting-expected.html": [
-      "b4b365c7a9dfa25363acfb3123b1c019c3ca08d0",
-      []
-     ]
-    },
-    "resources": {
-     "helpers.js": [
-      "256f0c880408c3343d36392f8b4cf64d9bbbfbe6",
-      []
-     ]
-    }
-   },
    "storage": {
     "META.yml": [
      "2aad1fb513710e839ad86c923bf208dae604d3d2",
@@ -373249,7 +373214,7 @@
      ]
     ],
     "beacon-cors.sub.window.js": [
-     "4a8e4dfbc6570e58ae7d57e409d4fbbc72a47964",
+     "5543bddc5f66b3a09c54937c0cf665d2d25ea8d6",
      [
       "beacon/beacon-cors.sub.window.html",
       {
@@ -373299,7 +373264,7 @@
      ]
     ],
     "beacon-preflight-failure.sub.window.js": [
-     "27e6905a9bd95a78621fe86d07d3671f95af111e",
+     "c5a2d813f176adc42d3ce3b6feeea2b6e34e9c69",
      [
       "beacon/beacon-preflight-failure.sub.window.html",
       {
@@ -373323,10 +373288,10 @@
       {}
      ]
     ],
-    "beacon-redirect.window.js": [
-     "3a8aef3c742b68348fa2c27303e297e8386768b3",
+    "beacon-redirect.sub.window.js": [
+     "fd23a45f86badfc1d540de414cb351c4e5ef06bb",
      [
-      "beacon/beacon-redirect.window.html",
+      "beacon/beacon-redirect.sub.window.html",
       {
        "script_metadata": [
         [
@@ -431060,7 +431025,7 @@
       ]
      ],
      "none.https.html": [
-      "e603753084cf2c3c85b0187a7a8f66b3de8cf401",
+      "548525968352147dc14ceeeab1ad6b6a93b2729a",
       [
        null,
        {
@@ -529186,82 +529151,6 @@
      ]
     ]
    },
-   "std-toast": {
-    "actions.html": [
-     "6a80def09985f27867f2c41bbb138b1a40399641",
-     [
-      null,
-      {}
-     ]
-    ],
-    "attributes.html": [
-     "9b87280b6688b3847401ea7b97ed63f6164bf70a",
-     [
-      null,
-      {}
-     ]
-    ],
-    "closebutton.html": [
-     "d53c78aca5da605bece2433c3796d8b1197e848e",
-     [
-      null,
-      {}
-     ]
-    ],
-    "events-open.html": [
-     "a49414d2fce2061bcc1399e222cd6b2b5ccdc872",
-     [
-      null,
-      {}
-     ]
-    ],
-    "events-showhide.html": [
-     "547f742f713cbf4c46a82ae1df353aa317b2d2df",
-     [
-      null,
-      {}
-     ]
-    ],
-    "methods.html": [
-     "981b9fba4341e5798c7456e02da53e97bd1369f3",
-     [
-      null,
-      {}
-     ]
-    ],
-    "options.html": [
-     "0383d71f9ae9ff9c2f682abd8158b9c2e31e245b",
-     [
-      null,
-      {
-       "timeout": "long"
-      }
-     ]
-    ],
-    "reflection.html": [
-     "36cbaf652287dbbde5a871b398d313cf70d1b275",
-     [
-      null,
-      {
-       "timeout": "long"
-      }
-     ]
-    ],
-    "show-toast.html": [
-     "50cdc2c06ddbf34b16119f9c42e3a7cbaf5ec258",
-     [
-      null,
-      {}
-     ]
-    ],
-    "styles.html": [
-     "1db8620485dc459577649e0c2689194d106dcc51",
-     [
-      null,
-      {}
-     ]
-    ]
-   },
    "storage": {
     "estimate-indexeddb.https.any.js": [
      "c62f5a96c1a2c22142988eabd5b59ce3d3409f95",
@@ -551948,7 +551837,7 @@
      ]
     ],
     "RTCDTMFSender-insertDTMF.https.html": [
-     "ac27c5139ccb12715d51cbd8f5ecdd83c40c23d1",
+     "71cfe70171f7ff4aeddd01483fce6edbf29e59b9",
      [
       null,
       {}
@@ -552252,6 +552141,13 @@
       {}
      ]
     ],
+    "RTCPeerConnection-operations.https.html": [
+     "e88c8b28172c1c0edbfaef4dda10a306470ad96f",
+     [
+      null,
+      {}
+     ]
+    ],
     "RTCPeerConnection-remote-track-mute.https.html": [
      "c280a7d44d8d2a477f2600c741ed68903e516651",
      [
@@ -552304,7 +552200,7 @@
      ]
     ],
     "RTCPeerConnection-setLocalDescription-parameterless.https.html": [
-     "0cce78bfbca161016721c4e2b122382c4be868f7",
+     "5a7a76319a0571961d7dacc3d1562327089587bd",
      [
       null,
       {}
diff --git a/tests/wpt/metadata/css/CSS2/floats/hit-test-floats-004.html.ini b/tests/wpt/metadata/css/CSS2/floats/hit-test-floats-004.html.ini
deleted file mode 100644
index 4bfb0c2053a..00000000000
--- a/tests/wpt/metadata/css/CSS2/floats/hit-test-floats-004.html.ini
+++ /dev/null
@@ -1,4 +0,0 @@
-[hit-test-floats-004.html]
-  [Miss float below something else]
-    expected: FAIL
-
diff --git a/tests/wpt/metadata/css/css-transitions/no-transition-from-ua-to-blocking-stylesheet.html.ini b/tests/wpt/metadata/css/css-transitions/no-transition-from-ua-to-blocking-stylesheet.html.ini
index e35a452a186..70a00a101f6 100644
--- a/tests/wpt/metadata/css/css-transitions/no-transition-from-ua-to-blocking-stylesheet.html.ini
+++ b/tests/wpt/metadata/css/css-transitions/no-transition-from-ua-to-blocking-stylesheet.html.ini
@@ -1,2 +1,2 @@
 [no-transition-from-ua-to-blocking-stylesheet.html]
-  expected: TIMEOUT
+  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-removeListener.html.ini b/tests/wpt/metadata/css/cssom-view/MediaQueryList-addListener-removeListener.html.ini
index 628b1fab770..c884dc82eab 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
@@ -2,3 +2,6 @@
   [listeners are called when <iframe> is resized]
     expected: FAIL
 
+  [listeners are called correct number of times]
+    expected: FAIL
+
diff --git a/tests/wpt/metadata/css/cssom-view/elementFromPosition.html.ini b/tests/wpt/metadata/css/cssom-view/elementFromPosition.html.ini
index 5733d536fd3..85e94926cb3 100644
--- a/tests/wpt/metadata/css/cssom-view/elementFromPosition.html.ini
+++ b/tests/wpt/metadata/css/cssom-view/elementFromPosition.html.ini
@@ -21,6 +21,3 @@
   [test the top of layer]
     expected: FAIL
 
-  [test some point of the element: top left corner]
-    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 bb8ba7c6ad9..0af08ed6710 100644
--- a/tests/wpt/metadata/fetch/content-type/response.window.js.ini
+++ b/tests/wpt/metadata/fetch/content-type/response.window.js.ini
@@ -312,18 +312,9 @@
   [fetch(): separate response Content-Type: text/plain ]
     expected: NOTRUN
 
-  [<iframe>: combined response Content-Type: text/html */*;charset=gbk]
-    expected: FAIL
-
-  [<iframe>: combined response Content-Type: text/html */*]
-    expected: FAIL
-
-  [<iframe>: combined response Content-Type: text/html;" text/plain]
-    expected: FAIL
-
-  [<iframe>: separate response Content-Type: text/html */*;charset=gbk]
-    expected: FAIL
-
   [<iframe>: separate response Content-Type: text/html;" \\" text/plain]
     expected: FAIL
 
+  [<iframe>: separate response Content-Type: text/html;" text/plain]
+    expected: FAIL
+
diff --git a/tests/wpt/metadata/fetch/content-type/script.window.js.ini b/tests/wpt/metadata/fetch/content-type/script.window.js.ini
index 279734168dc..a1ec6ff3aa3 100644
--- a/tests/wpt/metadata/fetch/content-type/script.window.js.ini
+++ b/tests/wpt/metadata/fetch/content-type/script.window.js.ini
@@ -53,9 +53,9 @@
   [combined text/javascript ]
     expected: FAIL
 
-  [separate text/javascript x/x]
-    expected: FAIL
-
   [separate text/javascript;charset=windows-1252  text/javascript]
     expected: FAIL
 
+  [separate text/javascript error]
+    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 61682d248e2..369bf4d4fa4 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 +11,6 @@
   [X-Content-Type-Options%3A%20nosniff%2C%2C%40%23%24%23%25%25%26%5E%26%5E*()()11!]
     expected: FAIL
 
-  [X-Content-Type-Options%3A%20%40%23%24%23%25%25%26%5E%26%5E*()()11!%2Cnosniff]
+  [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
new file mode 100644
index 00000000000..87b07c3e670
--- /dev/null
+++ b/tests/wpt/metadata/html/browsers/history/the-history-interface/traverse_the_history_1.html.ini
@@ -0,0 +1,4 @@
+[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_4.html.ini
deleted file mode 100644
index 385376c7321..00000000000
--- a/tests/wpt/metadata/html/browsers/history/the-history-interface/traverse_the_history_4.html.ini
+++ /dev/null
@@ -1,4 +0,0 @@
-[traverse_the_history_4.html]
-  [Multiple history traversals, last would be aborted]
-    expected: FAIL
-
diff --git a/tests/wpt/metadata/html/browsers/history/the-history-interface/traverse_the_history_3.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_3.html.ini
rename to tests/wpt/metadata/html/browsers/history/the-history-interface/traverse_the_history_5.html.ini
index 51f8272a6de..dc2e45516de 100644
--- a/tests/wpt/metadata/html/browsers/history/the-history-interface/traverse_the_history_3.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_3.html]
+[traverse_the_history_5.html]
   [Multiple history traversals, last would be aborted]
     expected: FAIL
 
diff --git a/tests/wpt/metadata/html/semantics/embedded-content/the-iframe-element/iframe_sandbox_popups_nonescaping-3.html.ini b/tests/wpt/metadata/html/semantics/embedded-content/the-iframe-element/iframe_sandbox_popups_nonescaping-3.html.ini
index e440b1e38c6..71edac2c5ed 100644
--- a/tests/wpt/metadata/html/semantics/embedded-content/the-iframe-element/iframe_sandbox_popups_nonescaping-3.html.ini
+++ b/tests/wpt/metadata/html/semantics/embedded-content/the-iframe-element/iframe_sandbox_popups_nonescaping-3.html.ini
@@ -1,6 +1,6 @@
 [iframe_sandbox_popups_nonescaping-3.html]
   type: testharness
-  expected: TIMEOUT
+  expected: CRASH
   [Check that popups from a sandboxed iframe do not escape the sandbox]
     expected: NOTRUN
 
diff --git a/tests/wpt/metadata/webaudio/the-audio-api/the-analysernode-interface/realtimeanalyser-fft-scaling.html.ini b/tests/wpt/metadata/webaudio/the-audio-api/the-analysernode-interface/realtimeanalyser-fft-scaling.html.ini
index 66bd350083b..a56bad443a2 100644
--- a/tests/wpt/metadata/webaudio/the-audio-api/the-analysernode-interface/realtimeanalyser-fft-scaling.html.ini
+++ b/tests/wpt/metadata/webaudio/the-audio-api/the-analysernode-interface/realtimeanalyser-fft-scaling.html.ini
@@ -1,4 +1,5 @@
 [realtimeanalyser-fft-scaling.html]
+  expected: TIMEOUT
   [X 2048-point FFT peak position is not equal to 64. Got 0.]
     expected: FAIL
 
diff --git a/tests/wpt/metadata/webaudio/the-audio-api/the-audiobuffersourcenode-interface/audiobuffersource-multi-channels.html.ini b/tests/wpt/metadata/webaudio/the-audio-api/the-audiobuffersourcenode-interface/audiobuffersource-multi-channels.html.ini
index f1db5900b81..601831e0fda 100644
--- a/tests/wpt/metadata/webaudio/the-audio-api/the-audiobuffersourcenode-interface/audiobuffersource-multi-channels.html.ini
+++ b/tests/wpt/metadata/webaudio/the-audio-api/the-audiobuffersourcenode-interface/audiobuffersource-multi-channels.html.ini
@@ -23,3 +23,6 @@
   [X Rendered audio for channel 5 does not equal [0,0.0626220703125,0.125030517578125,0.18695068359375,0.24810791015625,0.308319091796875,0.3673095703125,0.42486572265625,0.480743408203125,0.53472900390625,0.58660888671875,0.636199951171875,0.68328857421875,0.727691650390625,0.76922607421875,0.8077392578125...\] with an element-wise tolerance of {"absoluteThreshold":0.000030517578125,"relativeThreshold":0}.\n\tIndex\tActual\t\t\tExpected\t\tAbsError\t\tRelError\t\tTest threshold\n\t[1\]\t3.6732959747314453e-1\t6.2622070312500000e-2\t3.0470752716064453e-1\t4.8658168859649127e+0\t3.0517578125000000e-5\n\t[2\]\t6.8329977989196777e-1\t1.2503051757812500e-1\t5.5826926231384277e-1\t4.4650639949963384e+0\t3.0517578125000000e-5\n\t[3\]\t9.0373212099075317e-1\t1.8695068359375000e-1\t7.1678143739700317e-1\t3.8340669508039502e+0\t3.0517578125000000e-5\n\t[4\]\t9.9780619144439697e-1\t2.4810791015625000e-1\t7.4969828128814697e-1\t3.0216621502152523e+0\t3.0517578125000000e-5\n\t[5\]\t9.5236867666244507e-1\t3.0831909179687500e-1\t6.4404958486557007e-1\t2.0889059484187866e+0\t3.0517578125000000e-5\n\t...and 44048 more errors.\n\tMax AbsError of 1.9986916780471802e+0 at index of 29020.\n\t[29020\]\t9.9994289875030518e-1\t-9.9874877929687500e-1\t1.9986916780471802e+0\t2.0011956154322119e+0\t3.0517578125000000e-5\n\tMax RelError of Infinity at index of 10584.\n\t[10584\]\t-5.8778524398803711e-1\t0.0000000000000000e+0\t5.8778524398803711e-1\tInfinity\t3.0517578125000000e-5\n]
     expected: FAIL
 
+  [X Rendered audio for channel 5 does not equal [0,0.0626220703125,0.125030517578125,0.18695068359375,0.24810791015625,0.308319091796875,0.3673095703125,0.42486572265625,0.480743408203125,0.53472900390625,0.58660888671875,0.636199951171875,0.68328857421875,0.727691650390625,0.76922607421875,0.8077392578125...\] with an element-wise tolerance of {"absoluteThreshold":0.000030517578125,"relativeThreshold":0}.\n\tIndex\tActual\t\t\tExpected\t\tAbsError\t\tRelError\t\tTest threshold\n\t[1\]\t3.6732959747314453e-1\t6.2622070312500000e-2\t3.0470752716064453e-1\t4.8658168859649127e+0\t3.0517578125000000e-5\n\t[2\]\t6.8329977989196777e-1\t1.2503051757812500e-1\t5.5826926231384277e-1\t4.4650639949963384e+0\t3.0517578125000000e-5\n\t[3\]\t9.0373212099075317e-1\t1.8695068359375000e-1\t7.1678143739700317e-1\t3.8340669508039502e+0\t3.0517578125000000e-5\n\t[4\]\t9.9780619144439697e-1\t2.4810791015625000e-1\t7.4969828128814697e-1\t3.0216621502152523e+0\t3.0517578125000000e-5\n\t[5\]\t9.5236867666244507e-1\t3.0831909179687500e-1\t6.4404958486557007e-1\t2.0889059484187866e+0\t3.0517578125000000e-5\n\t...and 44056 more errors.\n\tMax AbsError of 1.9999977350234985e+0 at index of 10361.\n\t[10361\]\t9.9999773502349854e-1\t-1.0000000000000000e+0\t1.9999977350234985e+0\t1.9999977350234985e+0\t3.0517578125000000e-5\n\tMax RelError of Infinity at index of 7056.\n\t[7056\]\t5.8778524398803711e-1\t0.0000000000000000e+0\t5.8778524398803711e-1\tInfinity\t3.0517578125000000e-5\n]
+    expected: FAIL
+
diff --git a/tests/wpt/metadata/webaudio/the-audio-api/the-audiobuffersourcenode-interface/sub-sample-buffer-stitching.html.ini b/tests/wpt/metadata/webaudio/the-audio-api/the-audiobuffersourcenode-interface/sub-sample-buffer-stitching.html.ini
index 06f0da3d734..05e13f78c22 100644
--- a/tests/wpt/metadata/webaudio/the-audio-api/the-audiobuffersourcenode-interface/sub-sample-buffer-stitching.html.ini
+++ b/tests/wpt/metadata/webaudio/the-audio-api/the-audiobuffersourcenode-interface/sub-sample-buffer-stitching.html.ini
@@ -152,3 +152,9 @@
   [X Stitched sine-wave buffers at sample rate 43800 does not equal [0,0.06264832615852356,0.12505052983760834,0.18696144223213196,0.24813786149024963,0.308339387178421,0.36732959747314453,0.4248766601085663,0.480754554271698,0.5347436666488647,0.5866320133209229,0.6362156271934509,0.6832997798919678,0.7276994585990906,0.7692402601242065,0.8077589869499207...\] with an element-wise tolerance of {"absoluteThreshold":0.0038986,"relativeThreshold":0}.\n\tIndex\tActual\t\t\tExpected\t\tAbsError\t\tRelError\t\tTest threshold\n\t[19030\]\t-6.4853054482227890e-8\t-7.3546999692916870e-1\t7.3546993207611422e-1\t9.9999991182093795e-1\t3.8985999999999999e-3\n\t[19031\]\t-3.6017334461212158e-1\t-6.9157749414443970e-1\t3.3140414953231812e-1\t4.7920030992665957e-1\t3.8985999999999999e-3\n\t[38059\]\t-1.5015864107681409e-7\t-9.8956179618835449e-1\t9.8956164602971342e-1\t9.9999984825743915e-1\t3.8985999999999999e-3\n\t[38060\]\t-8.8409073650836945e-2\t-9.9664616584777832e-1\t9.0823709219694138e-1\t9.1129341918891205e-1\t3.8985999999999999e-3\n\tMax AbsError of 9.8956164602971342e-1 at index of 38059.\n\tMax RelError of 9.9999991182093795e-1 at index of 19030.\n]
     expected: FAIL
 
+  [X SNR (39.5689338967812 dB) is not greater than or equal to 65.737. Got 39.5689338967812.]
+    expected: FAIL
+
+  [X Stitched sine-wave buffers at sample rate 43800 does not equal [0,0.06264832615852356,0.12505052983760834,0.18696144223213196,0.24813786149024963,0.308339387178421,0.36732959747314453,0.4248766601085663,0.480754554271698,0.5347436666488647,0.5866320133209229,0.6362156271934509,0.6832997798919678,0.7276994585990906,0.7692402601242065,0.8077589869499207...\] with an element-wise tolerance of {"absoluteThreshold":0.0038986,"relativeThreshold":0}.\n\tIndex\tActual\t\t\tExpected\t\tAbsError\t\tRelError\t\tTest threshold\n\t[19030\]\t-4.2493608780205250e-3\t-7.3546999692916870e-1\t7.3122063605114818e-1\t9.9422225121927066e-1\t3.8985999999999999e-3\n\t[19031\]\t-3.6017334461212158e-1\t-6.9157749414443970e-1\t3.3140414953231812e-1\t4.7920030992665957e-1\t3.8985999999999999e-3\n\t[38059\]\t-9.8401503637433052e-3\t-9.8956179618835449e-1\t9.7972164582461119e-1\t9.9005605268751673e-1\t3.8985999999999999e-3\n\t[38060\]\t-8.8409073650836945e-2\t-9.9664616584777832e-1\t9.0823709219694138e-1\t9.1129341918891205e-1\t3.8985999999999999e-3\n\tMax AbsError of 9.7972164582461119e-1 at index of 38059.\n\tMax RelError of 9.9422225121927066e-1 at index of 19030.\n]
+    expected: FAIL
+
diff --git a/tests/wpt/metadata/webmessaging/with-ports/017.html.ini b/tests/wpt/metadata/webmessaging/without-ports/017.html.ini
similarity index 100%
rename from tests/wpt/metadata/webmessaging/with-ports/017.html.ini
rename to tests/wpt/metadata/webmessaging/without-ports/017.html.ini
diff --git a/tests/wpt/metadata/webmessaging/without-ports/018.html.ini b/tests/wpt/metadata/webmessaging/without-ports/018.html.ini
deleted file mode 100644
index 663a1f8fa30..00000000000
--- a/tests/wpt/metadata/webmessaging/without-ports/018.html.ini
+++ /dev/null
@@ -1,5 +0,0 @@
-[018.html]
-  expected: TIMEOUT
-  [origin of the script that invoked the method, javascript:]
-    expected: TIMEOUT
-
diff --git a/tests/wpt/web-platform-tests/beacon/beacon-common.sub.js b/tests/wpt/web-platform-tests/beacon/beacon-common.sub.js
index ae2f169f272..3635da73b75 100644
--- a/tests/wpt/web-platform-tests/beacon/beacon-common.sub.js
+++ b/tests/wpt/web-platform-tests/beacon/beacon-common.sub.js
@@ -16,33 +16,33 @@ var largePayload = largePayloadSize + ":" + Array(largePayloadSize).fill('*').jo
 var maxPayload = (maxPayloadSize - 6) + ":" + Array(maxPayloadSize - 6).fill('*').join("")
 
 // Test case definitions.
-//      id: String containing the unique name of the test case.
+//      name: String containing the unique name of the test case.
 //      data: Payload object to send through sendbeacon.
-var noDataTest = { id: "NoData" };
-var nullDataTest = { id: "NullData", data: null };
-var undefinedDataTest = { id: "UndefinedData", data: undefined };
-var smallStringTest = { id: "SmallString", data: smallPayload };
-var mediumStringTest = { id: "MediumString", data: mediumPayload };
-var largeStringTest = { id: "LargeString", data: largePayload };
-var maxStringTest = { id: "MaxString", data: maxPayload };
-var emptyBlobTest = { id: "EmptyBlob", data: new Blob() };
-var smallBlobTest = { id: "SmallBlob", data: new Blob([smallPayload]) };
-var mediumBlobTest = { id: "MediumBlob", data: new Blob([mediumPayload]) };
-var largeBlobTest = { id: "LargeBlob", data: new Blob([largePayload]) };
-var maxBlobTest = { id: "MaxBlob", data: new Blob([maxPayload]) };
-var emptyBufferSourceTest = { id: "EmptyBufferSource", data: new Uint8Array() };
-var smallBufferSourceTest = { id: "SmallBufferSource", data: CreateArrayBufferFromPayload(smallPayload) };
-var mediumBufferSourceTest = { id: "MediumBufferSource", data: CreateArrayBufferFromPayload(mediumPayload) };
-var largeBufferSourceTest = { id: "LargeBufferSource", data: CreateArrayBufferFromPayload(largePayload) };
-var maxBufferSourceTest = { id: "MaxBufferSource", data: CreateArrayBufferFromPayload(maxPayload) };
-var emptyFormDataTest = { id: "EmptyFormData", data: CreateEmptyFormDataPayload() };
-var smallFormDataTest = { id: "SmallFormData", data: CreateFormDataFromPayload(smallPayload) };
-var mediumFormDataTest = { id: "MediumFormData", data: CreateFormDataFromPayload(mediumPayload) };
-var largeFormDataTest = { id: "LargeFormData", data: CreateFormDataFromPayload(largePayload) };
-var smallSafeContentTypeEncodedTest = { id: "SmallSafeContentTypeEncoded", data: new Blob([smallPayload], { type: 'application/x-www-form-urlencoded' }) };
-var smallSafeContentTypeFormTest = { id: "SmallSafeContentTypeForm", data: new FormData() };
-var smallSafeContentTypeTextTest = { id: "SmallSafeContentTypeText", data: new Blob([smallPayload], { type: 'text/plain' }) };
-var smallCORSContentTypeTextTest = { id: "SmallCORSContentTypeText", data: new Blob([smallPayload], { type: 'text/html' }) };
+var noDataTest = { name: "NoData" };
+var nullDataTest = { name: "NullData", data: null };
+var undefinedDataTest = { name: "UndefinedData", data: undefined };
+var smallStringTest = { name: "SmallString", data: smallPayload };
+var mediumStringTest = { name: "MediumString", data: mediumPayload };
+var largeStringTest = { name: "LargeString", data: largePayload };
+var maxStringTest = { name: "MaxString", data: maxPayload };
+var emptyBlobTest = { name: "EmptyBlob", data: new Blob() };
+var smallBlobTest = { name: "SmallBlob", data: new Blob([smallPayload]) };
+var mediumBlobTest = { name: "MediumBlob", data: new Blob([mediumPayload]) };
+var largeBlobTest = { name: "LargeBlob", data: new Blob([largePayload]) };
+var maxBlobTest = { name: "MaxBlob", data: new Blob([maxPayload]) };
+var emptyBufferSourceTest = { name: "EmptyBufferSource", data: new Uint8Array() };
+var smallBufferSourceTest = { name: "SmallBufferSource", data: CreateArrayBufferFromPayload(smallPayload) };
+var mediumBufferSourceTest = { name: "MediumBufferSource", data: CreateArrayBufferFromPayload(mediumPayload) };
+var largeBufferSourceTest = { name: "LargeBufferSource", data: CreateArrayBufferFromPayload(largePayload) };
+var maxBufferSourceTest = { name: "MaxBufferSource", data: CreateArrayBufferFromPayload(maxPayload) };
+var emptyFormDataTest = { name: "EmptyFormData", data: CreateEmptyFormDataPayload() };
+var smallFormDataTest = { name: "SmallFormData", data: CreateFormDataFromPayload(smallPayload) };
+var mediumFormDataTest = { name: "MediumFormData", data: CreateFormDataFromPayload(mediumPayload) };
+var largeFormDataTest = { name: "LargeFormData", data: CreateFormDataFromPayload(largePayload) };
+var smallSafeContentTypeEncodedTest = { name: "SmallSafeContentTypeEncoded", data: new Blob([smallPayload], { type: 'application/x-www-form-urlencoded' }) };
+var smallSafeContentTypeFormTest = { name: "SmallSafeContentTypeForm", data: new FormData() };
+var smallSafeContentTypeTextTest = { name: "SmallSafeContentTypeText", data: new Blob([smallPayload], { type: 'text/plain' }) };
+var smallCORSContentTypeTextTest = { name: "SmallCORSContentTypeText", data: new Blob([smallPayload], { type: 'text/html' }) };
 // We don't test maxFormData because the extra multipart separators make it difficult to
 // calculate a maxPayload.
 
@@ -66,13 +66,6 @@ var sampleTests = [noDataTest, nullDataTest, undefinedDataTest, smallStringTest,
 
 var preflightTests = [smallCORSContentTypeTextTest];
 
-// Build a test lookup table, which is useful when instructing a web worker or an iframe
-// to run a test, so that we don't have to marshal the entire test case across a process boundary.
-var testLookup = {};
-allTests.forEach(function(testCase) {
-    testLookup[testCase.id] = testCase;
-});
-
 // Helper function to create an ArrayBuffer representation of a string.
 function CreateArrayBufferFromPayload(payload) {
     var length = payload.length;
@@ -105,76 +98,27 @@ function CreateFormDataFromPayload(payload) {
     return formData;
 }
 
-// Initializes a session with a client-generated SID.
-// A "session" is a run of one or more tests. It is used to batch several beacon
-// tests in a way that isolates the server-side session state and makes it easy
-// to poll the results of the tests in one request.
-//     testCases: The array of test cases participating in the session.
-function initSession(testCases) {
-    return {
-        // Provides a unique session identifier to prevent mixing server-side data
-        // with other sessions.
-        id: self.token(),
-        // Dictionary of test name to live testCase object.
-        testCaseLookup: {},
-        // Array of testCase objects for iteration.
-        testCases: [],
-        // Tracks the total number of tests in the session.
-        totalCount: testCases.length,
-        // Tracks the number of tests for which we have sent the beacon.
-        // When it reaches totalCount, we will start polling for results.
-        sentCount: 0,
-        // Tracks the number of tests for which we have verified the results.
-        // When it reaches sentCount, we will stop polling for results.
-        doneCount: 0,
-        // Helper to add a testCase to the session.
-        add: function add(testCase) {
-            this.testCases.push(testCase);
-            this.testCaseLookup[testCase.id] = testCase;
-        }
+// Schedules async_test's for each of the test cases, treating them as a single session,
+// and wires up the continueAfterSendingBeacon() and waitForResults() calls.
+// Parameters:
+//     testCases: An array of test cases.
+//     suffix [optional]: A string used for the suffix for each test case name.
+//     buildUrl [optional]: A function that returns a beacon URL given an id.
+//     sendData [optional]: A function that sends the beacon with given a URL and payload.
+function runTests(testCases, suffix = '', buildUrl = self.buildUrl, sendData = self.sendData) {
+    for (const testCase of testCases) {
+        const id = token();
+        async_test((test) => {
+            const url = buildUrl(id);
+            assert_true(sendData(url, testCase.data), 'sendBeacon should succeed');
+            waitForResult(id).then(() => test.done(), test.step_func((e) => {throw e;}));
+        }, `Verify 'navigator.sendbeacon()' successfully sends for variant: ${testCase.name}${suffix}`);
     };
 }
 
-// Schedules async_test's for each of the test cases, treating them as a single session,
-// and wires up the continueAfterSendingBeacon() and waitForResults() calls.
-// The method looks for several "extension" functions in the global scope:
-//   - self.buildBaseUrl: if present, can change the base URL of a beacon target URL (this
-//     is the scheme, hostname, and port).
-//   - self.buildTargetUrl: if present, can modify a beacon target URL (for example wrap it).
-// Parameters:
-//     testCases: An array of test cases.
-//     sendData [optional]: A function that sends the beacon.
-function runTests(testCases, sendData = self.sendData) {
-    const session = initSession(testCases);
-
-    testCases.forEach(function(testCase, testIndex) {
-        // Make a copy of the test case as we'll be storing some metadata on it,
-        // such as which session it belongs to.
-        const testCaseCopy = Object.assign({ session: session }, testCase);
-
-        testCaseCopy.index = testIndex;
-
-        async_test((test) => {
-            // Save the testharness.js 'test' object, so that we only have one object
-            // to pass around.
-            testCaseCopy.test = test;
-
-            // Extension point: generate the beacon URL.
-            var baseUrl = "http://{{host}}:{{ports[http][0]}}";
-            if (self.buildBaseUrl) {
-                baseUrl = self.buildBaseUrl(baseUrl);
-            }
-            var targetUrl = `${baseUrl}/beacon/resources/beacon.py?cmd=store&sid=${session.id}&tid=${testCaseCopy.id}&tidx=${testIndex}`;
-            if (self.buildTargetUrl) {
-                targetUrl = self.buildTargetUrl(targetUrl);
-            }
-            // Attach the URL to the test object for debugging purposes.
-            testCaseCopy.url = targetUrl;
-
-            assert_true(sendData(testCaseCopy), 'sendBeacon should succeed');
-            waitForResult(testCaseCopy).then(() => test.done(), test.step_func((e) => {throw e;}));
-        }, `Verify 'navigator.sendbeacon()' successfully sends for variant: ${testCaseCopy.id}`);
-    });
+function buildUrl(id) {
+    const baseUrl = "http://{{host}}:{{ports[http][0]}}";
+    return `${baseUrl}/beacon/resources/beacon.py?cmd=store&id=${id}`;
 }
 
 // Sends the beacon for a single test. This step is factored into its own function so that
@@ -183,15 +127,13 @@ function runTests(testCases, sendData = self.sendData) {
 // full testharness.js test context. Instead return 'false', and the main scope will fail
 // the test.
 // Returns the result of the 'sendbeacon()' function call, true or false.
-function sendData(testCase) {
-    return self.navigator.sendBeacon(testCase.url, testCase.data);
+function sendData(url, payload) {
+    return self.navigator.sendBeacon(url, payload);
 }
 
 // Poll the server for the test result.
-async function waitForResult(testCase) {
-    const session = testCase.session;
-    const index = testCase.index;
-    const url = `resources/beacon.py?cmd=stat&sid=${session.id}&tidx_min=${index}&tidx_max=${index}`;
+async function waitForResult(id) {
+    const url = `resources/beacon.py?cmd=stat&id=${id}`;
     for (let i = 0; i < 30; ++i) {
         const response = await fetch(url);
         const text = await response.text();
@@ -218,16 +160,10 @@ function runSendInIframeAndNavigateTests() {
     iframe.onload = function() {
         // Clear our onload handler to prevent re-running the tests as we navigate away.
         iframe.onload = null;
-        function sendData(testCase) {
-            return iframe.contentWindow.navigator.sendBeacon(testCase.url, testCase.data);
+        function sendData(url, payload) {
+            return iframe.contentWindow.navigator.sendBeacon(url, payload);
         }
-        const tests = [];
-        for (const test of sampleTests) {
-            const copy = Object.assign({}, test);
-            copy.id = `${test.id}-NAVIGATE`;
-            tests.push(copy);
-        }
-        runTests(tests, sendData);
+        runTests(sampleTests, '-NAVIGATE', self.buildUrl, sendData);
         // Now navigate ourselves.
         iframe.contentWindow.location = "http://{{host}}:{{ports[http][0]}}/";
     };
diff --git a/tests/wpt/web-platform-tests/beacon/beacon-cors.sub.window.js b/tests/wpt/web-platform-tests/beacon/beacon-cors.sub.window.js
index 4a8e4dfbc65..5543bddc5f6 100644
--- a/tests/wpt/web-platform-tests/beacon/beacon-cors.sub.window.js
+++ b/tests/wpt/web-platform-tests/beacon/beacon-cors.sub.window.js
@@ -8,15 +8,8 @@
 // the beacon handler will return CORS headers. This test ensures that the
 // sendBeacon() succeeds in either case.
 [true, false].forEach(function(allowCors) {
-    // Implement the self.buildBaseUrl and self.buildTargetUrl extensions
-    // to change the target URL to use a cross-origin domain name.
-    self.buildBaseUrl = function(baseUrl) {
-        return "http://{{domains[www]}}:{{ports[http][0]}}";
-    };
-    // Implement the self.buildTargetUrl extension to append a directive
-    // to the handler, that it should return CORS headers, if 'allowCors'
-    // is true.
-    self.buildTargetUrl = function(targetUrl) {
+    function buildUrl(id) {
+        const baseUrl = "http://{{domains[www]}}:{{ports[http][0]}}";
         // Note that 'allowCors=true' is not necessary for the sendBeacon() to reach
         // the server. Beacons use the HTTP POST method, which is a CORS-safelisted
         // method, and thus they do not trigger preflight. If the server does not
@@ -27,16 +20,10 @@
         // value of the sendBeacon() call, because the underlying fetch is asynchronous.
         // The "Beacon CORS" tests are merely testing that sendBeacon() to a cross-
         // origin URL *will* work regardless.
-        return allowCors ? `${targetUrl}&origin=http://{{host}}:{{ports[http][0]}}&credentials=true` : targetUrl;
+        const additionalQuery = allowCors ? "&origin=http://{{host}}:{{ports[http][0]}}&credentials=true" : "";
+        return `${baseUrl}/beacon/resources/beacon.py?cmd=store&id=${id}${additionalQuery}`
     }
-
-    const tests = [];
-    for (const test of sampleTests) {
-        const copy = Object.assign({}, test);
-        copy.id = `${test.id}-${allowCors ? "CORS-ALLOW" : "CORS-FORBID"}`;
-        tests.push(copy);
-    }
-    runTests(tests);
+    runTests(sampleTests, allowCors ? "-CORS-ALLOW" : "-CORS-FORBID", buildUrl);
 });
 
 // Now test a cross-origin request that doesn't use a safelisted Content-Type and ensure
@@ -44,24 +31,12 @@
 // header is used there should be a preflight/options request and we should only succeed
 // send the payload if the proper CORS headers are used.
 {
-    // Implement the self.buildBaseUrl and self.buildTargetUrl extensions
-    // to change the target URL to use a cross-origin domain name.
-    self.buildBaseUrl = function (baseUrl) {
-        return "http://{{domains[www]}}:{{ports[http][0]}}";
-    };
-
-    // Implement the self.buildTargetUrl extension to append a directive
-    // to the handler, that it should return CORS headers for the preflight we expect.
-    self.buildTargetUrl = function (targetUrl) {
-        return `${targetUrl}&origin=http://{{host}}:{{ports[http][0]}}&credentials=true&preflightExpected=true`;
+    function buildUrl(id) {
+        const baseUrl = "http://{{domains[www]}}:{{ports[http][0]}}";
+        const additionalQuery = "&origin=http://{{host}}:{{ports[http][0]}}&credentials=true&preflightExpected=true";
+        return `${baseUrl}/beacon/resources/beacon.py?cmd=store&id=${id}${additionalQuery}`
     }
-    const tests = [];
-    for (const test of preflightTests) {
-        const copy = Object.assign({}, test);
-        copy.id = `${test.id}-PREFLIGHT-ALLOW`;
-        tests.push(copy);
-    }
-    runTests(tests);
+    runTests(preflightTests, "-PREFLIGHT-ALLOW", buildUrl);
 }
 
 done();
diff --git a/tests/wpt/web-platform-tests/beacon/beacon-preflight-failure.sub.window.js b/tests/wpt/web-platform-tests/beacon/beacon-preflight-failure.sub.window.js
index 27e6905a9bd..c5a2d813f17 100644
--- a/tests/wpt/web-platform-tests/beacon/beacon-preflight-failure.sub.window.js
+++ b/tests/wpt/web-platform-tests/beacon/beacon-preflight-failure.sub.window.js
@@ -2,13 +2,10 @@
 // META: script=/common/get-host-info.sub.js
 
 promise_test(async (test) => {
-  const sid = token();
-  const tid = token();
   const origin = get_host_info().REMOTE_ORIGIN;
-  const store =
-    `${origin}/beacon/resources/beacon.py?cmd=store&sid=${sid}&tid=${tid}&tidx=0`;
-  const monitor =
-    `/beacon/resources/beacon.py?cmd=stat&sid=${sid}&tidx_min=0&tidx_max=0`;
+  const id = token();
+  const store = `${origin}/beacon/resources/beacon.py?cmd=store&id=${id}`;
+  const monitor = `/beacon/resources/beacon.py?cmd=stat&id=${id}`;
 
   assert_true(navigator.sendBeacon(store, new Blob([], {type: 'x/y'})));
 
@@ -25,7 +22,7 @@ promise_test(async (test) => {
   }
 
   const expected =
-    JSON.stringify([{id: tid, error: 'Preflight not expected.'}]);
+    JSON.stringify([{error: 'Preflight not expected.'}]);
 
   assert_equals(actual, expected);
 });
diff --git a/tests/wpt/web-platform-tests/beacon/beacon-redirect.window.js b/tests/wpt/web-platform-tests/beacon/beacon-redirect.sub.window.js
similarity index 54%
rename from tests/wpt/web-platform-tests/beacon/beacon-redirect.window.js
rename to tests/wpt/web-platform-tests/beacon/beacon-redirect.sub.window.js
index 3a8aef3c742..fd23a45f86b 100644
--- a/tests/wpt/web-platform-tests/beacon/beacon-redirect.window.js
+++ b/tests/wpt/web-platform-tests/beacon/beacon-redirect.sub.window.js
@@ -8,18 +8,13 @@
 // Note that status codes 307 and 308 are the only codes that will maintain POST data
 // through a redirect.
 [307, 308].forEach(function(status) {
-    // Implement the self.buildTargetUrl extension to inject a redirect to
-    // the sendBeacon target.
-    self.buildTargetUrl = function(targetUrl) {
+    function buildUrl(id) {
+        const baseUrl = "http://{{host}}:{{ports[http][0]}}";
+        const targetUrl = `${baseUrl}/beacon/resources/beacon.py?cmd=store&id=${id}`;
+
         return `/common/redirect.py?status=${status}&location=${encodeURIComponent(targetUrl)}`;
-    };
-    const tests = [];
-    for (const test of sampleTests) {
-        const copy = Object.assign({}, test);
-        copy.id = `${test.id}-${status}`;
-        tests.push(copy);
     }
-    runTests(tests);
+    runTests(sampleTests, `-${status}`, buildUrl);
 });
 
 done();
diff --git a/tests/wpt/web-platform-tests/beacon/resources/beacon.py b/tests/wpt/web-platform-tests/beacon/resources/beacon.py
index 5f2553d3c4d..34b55b1a95b 100644
--- a/tests/wpt/web-platform-tests/beacon/resources/beacon.py
+++ b/tests/wpt/web-platform-tests/beacon/resources/beacon.py
@@ -1,7 +1,5 @@
 import json
 
-def build_stash_key(session_id, test_num):
-    return "%s_%s" % (session_id, test_num)
 
 def main(request, response):
     """Helper handler for Beacon tests.
@@ -9,63 +7,50 @@ def main(request, response):
     It handles two forms of requests:
 
     STORE:
-        A URL with a query string of the form 'cmd=store&sid=<token>&tidx=<test_index>&tid=<test_name>'.
+        A URL with a query string of the form 'cmd=store&id=<token>'.
 
-        Stores the receipt of a sendBeacon() request along with its validation result, returning HTTP 200 OK.
+        Stores the receipt of a sendBeacon() request along with its validation
+        result, returning HTTP 200 OK.
 
-        Parameters:
-            tidx - the integer index of the test.
-            tid - a friendly identifier or name for the test, used when returning results.
+        if "preflightExpected"  exists in the query, this handler responds to
+        CORS preflights.
 
     STAT:
-        A URL with a query string of the form 'cmd=stat&sid=<token>&tidx_min=<min_test_index>&tidx_max=<max_test_index>'.
+        A URL with a query string of the form 'cmd=stat&id=<token>'.
 
-        Retrieves the results of test with indices [min_test_index, max_test_index] and returns them as
-        a JSON array and HTTP 200 OK status code. Due to the eventual read-once nature of the stash, results for a given test
-        are only guaranteed to be returned once, though they may be returned multiple times.
+        Retrieves the results of test for the given id and returns them as a
+        JSON array and HTTP 200 OK status code. Due to the eventual read-once
+        nature of the stash, results for a given test are only guaranteed to be
+        returned once, though they may be returned multiple times.
 
-        Parameters:
-            tidx_min - the lower-bounding integer test index.
-            tidx_max - the upper-bounding integer test index.
-
-        Example response body:
-            [{"id": "Test1", error: null}, {"id": "Test2", error: "some validation details"}]
+        Example response bodies:
+            - [{error: null}]
+            - [{error: "some validation details"}]
+            - []
 
     Common parameters:
         cmd - the command, 'store' or 'stat'.
-        sid - session id used to provide isolation to a test run comprising multiple sendBeacon()
-              tests.
+        id - the unique identifier of the test.
     """
 
-    session_id = request.GET.first("sid");
-    command = request.GET.first("cmd").lower();
-
-    # Workaround to circumvent the limitation that cache keys
-    # can only be UUID's.
-    def wrap_key(key, path):
-        return (str(path), str(key))
-    request.server.stash._wrap_key = wrap_key
+    id = request.GET.first("id")
+    command = request.GET.first("cmd").lower()
 
     # Append CORS headers if needed.
     if "origin" in request.GET:
-        response.headers.set("Access-Control-Allow-Origin", request.GET.first("origin"))
+        response.headers.set("Access-Control-Allow-Origin",
+                             request.GET.first("origin"))
     if "credentials" in request.GET:
-        response.headers.set("Access-Control-Allow-Credentials", request.GET.first("credentials"))
+        response.headers.set("Access-Control-Allow-Credentials",
+                             request.GET.first("credentials"))
 
     # Handle the 'store' and 'stat' commands.
     if command == "store":
-        # The test id is just used to make the results more human-readable.
-        test_id = request.GET.first("tid")
-        # The test index is used to build a predictable stash key, together
-        # with the unique session id, in order to retrieve a range of results
-        # later knowing the index range.
-        test_idx = request.GET.first("tidx")
-        test_data = { "id": test_id, "error": None }
+        error = None
 
-        # Only store the actual POST requests, not any preflight/OPTIONS requests we may get.
+        # Only store the actual POST requests, not any preflight/OPTIONS
+        # requests we may get.
         if request.method == "POST":
-            test_data_key = build_stash_key(session_id, test_idx)
-
             payload = ""
             if "Content-Type" in request.headers and \
                "form-data" in request.headers["Content-Type"]:
@@ -83,42 +68,38 @@ def main(request, response):
             if len(payload_parts) > 0:
                 payload_size = int(payload_parts[0])
 
-                # Confirm the payload size sent matches with the number of characters sent.
+                # Confirm the payload size sent matches with the number of
+                # characters sent.
                 if payload_size != len(payload_parts[1]):
-                    test_data["error"] = "expected %d characters but got %d" % (payload_size, len(payload_parts[1]))
+                    error = "expected %d characters but got %d" % (
+                        payload_size, len(payload_parts[1]))
                 else:
                     # Confirm the payload contains the correct characters.
                     for i in range(0, payload_size):
                         if payload_parts[1][i] != "*":
-                            test_data["error"] = "expected '*' at index %d but got '%s''" % (i, payload_parts[1][i])
+                            error = "expected '*' at index %d but got '%s''" % (
+                                i, payload_parts[1][i])
                             break
 
             # Store the result in the stash so that it can be retrieved
             # later with a 'stat' command.
-            request.server.stash.put(test_data_key, test_data)
+            request.server.stash.put(id, {"error": error})
         elif request.method == "OPTIONS":
-            # If we expect a preflight, then add the cors headers we expect, otherwise log an error as we shouldn't
-            # send a preflight for all requests.
+            # If we expect a preflight, then add the cors headers we expect,
+            # otherwise log an error as we shouldn't send a preflight for all
+            # requests.
             if "preflightExpected" in request.GET:
-                response.headers.set("Access-Control-Allow-Headers", "content-type")
+                response.headers.set("Access-Control-Allow-Headers",
+                                     "content-type")
                 response.headers.set("Access-Control-Allow-Methods", "POST")
             else:
-                test_data_key = build_stash_key(session_id, test_idx)
-                test_data["error"] = "Preflight not expected."
-                request.server.stash.put(test_data_key, test_data)
+                error = "Preflight not expected."
+                request.server.stash.put(id, {"error": error})
     elif command == "stat":
-        test_idx_min = int(request.GET.first("tidx_min"))
-        test_idx_max = int(request.GET.first("tidx_max"))
-
-        # For each result that has come in, append it to the response.
-        results = []
-        for test_idx in range(test_idx_min, test_idx_max+1): # +1 because end is exclusive
-            test_data_key = build_stash_key(session_id, test_idx)
-            test_data = request.server.stash.take(test_data_key)
-            if test_data:
-                results.append(test_data)
+        test_data = request.server.stash.take(id)
+        results = [test_data] if test_data else []
 
         response.headers.set("Content-Type", "text/plain")
         response.content = json.dumps(results)
     else:
-        response.status = 400 # BadRequest
\ No newline at end of file
+        response.status = 400  # BadRequest
diff --git a/tests/wpt/web-platform-tests/html/cross-origin-embedder-policy/none.https.html b/tests/wpt/web-platform-tests/html/cross-origin-embedder-policy/none.https.html
index e603753084c..54852596835 100644
--- a/tests/wpt/web-platform-tests/html/cross-origin-embedder-policy/none.https.html
+++ b/tests/wpt/web-platform-tests/html/cross-origin-embedder-policy/none.https.html
@@ -84,6 +84,8 @@ async_test(t => {
   assert_equals(win, null);
 }, `"require-corp" top-level noopener popup: navigating to "none" should succeed`);
 
+// CORP is checked because COEP of the frame is "require-corp". The parent
+// frame's COEP value doesn't matter.
 async_test(t => {
   const frame = document.createElement("iframe");
   const id = token();
@@ -94,8 +96,33 @@ async_test(t => {
       t.done();
     }
   }));
+  // REMOTE_ORIGIN is cross-origin, same-site.
+  frame.src = `${HOST.HTTPS_REMOTE_ORIGIN}${BASE}/navigate-require-corp-same-site.sub.html?token=${id}`;
+  document.body.append(frame);
+}, 'CORP: same-site is checked and allowed.');
+
+// CORP is checked because COEP of the frame is "require-corp". The parent
+// frame's COEP value doesn't matter.
+async_test(t => {
+  const frame = document.createElement("iframe");
+  const id = token();
+  t.add_cleanup(() => frame.remove());
+  let loaded = false;
+  window.addEventListener('message', t.step_func((e) => {
+    if (e.data === id) {
+        loaded = true;
+    }
+  }));
+  t.step_timeout(() => {
+    // Make sure the iframe didn't load. See https://github.com/whatwg/html/issues/125 for why a
+    // timeout is used here. Long term all network error handling should be similar and have a
+    // reliable event.
+    assert_false(loaded);
+    t.done();
+  }, 2000);
+
+  // NOTESAMESITE_ORIGIN is cross-origin, cross-site.
   frame.src = `${HOST.HTTPS_NOTSAMESITE_ORIGIN}${BASE}/navigate-require-corp-same-site.sub.html?token=${id}`;
   document.body.append(frame);
-}, 'CORP: same-site is not checked.');
-
+}, 'CORP: same-site is checked and blocked.');
 </script>
diff --git a/tests/wpt/web-platform-tests/html/cross-origin-opener-policy/resources/postback.html.headers b/tests/wpt/web-platform-tests/html/cross-origin-opener-policy/resources/postback.html.headers
index 6604450991a..4e798cd9f5d 100644
--- a/tests/wpt/web-platform-tests/html/cross-origin-opener-policy/resources/postback.html.headers
+++ b/tests/wpt/web-platform-tests/html/cross-origin-opener-policy/resources/postback.html.headers
@@ -1 +1,2 @@
 Cross-Origin-Embedder-Policy: require-corp
+Cross-Origin-Resource-Policy: cross-origin
diff --git a/tests/wpt/web-platform-tests/html/infrastructure/safe-passing-of-structured-data/resources/echo-iframe.html.headers b/tests/wpt/web-platform-tests/html/infrastructure/safe-passing-of-structured-data/resources/echo-iframe.html.headers
index 6604450991a..4e798cd9f5d 100644
--- a/tests/wpt/web-platform-tests/html/infrastructure/safe-passing-of-structured-data/resources/echo-iframe.html.headers
+++ b/tests/wpt/web-platform-tests/html/infrastructure/safe-passing-of-structured-data/resources/echo-iframe.html.headers
@@ -1 +1,2 @@
 Cross-Origin-Embedder-Policy: require-corp
+Cross-Origin-Resource-Policy: cross-origin
diff --git a/tests/wpt/web-platform-tests/std-toast/META.yml b/tests/wpt/web-platform-tests/std-toast/META.yml
deleted file mode 100644
index c54357a03f2..00000000000
--- a/tests/wpt/web-platform-tests/std-toast/META.yml
+++ /dev/null
@@ -1,5 +0,0 @@
-spec: https://github.com/jackbsteinberg/std-toast
-suggested_reviewers:
-  - domenic
-  - fergald
-  - jackbsteinberg
diff --git a/tests/wpt/web-platform-tests/std-toast/actions.html b/tests/wpt/web-platform-tests/std-toast/actions.html
deleted file mode 100644
index 6a80def0998..00000000000
--- a/tests/wpt/web-platform-tests/std-toast/actions.html
+++ /dev/null
@@ -1,190 +0,0 @@
-<!DOCTYPE html>
-<meta charset="utf-8">
-<title>Toast: action tests</title>
-
-<script src="/resources/testharness.js"></script>
-<script src="/resources/testharnessreport.js"></script>
-
-<main></main>
-
-<script type="module">
-import { testActionToast, testToastElement, assertActionButtonOnToast } from './resources/helpers.js';
-import { showToast } from 'std:elements/toast';
-
-testActionToast((toast) => {
-    assert_equals(toast.action.textContent, 'action');
-}, 'the action element gets properly captured with this.action');
-
-testActionToast((toast) => {
-    toast.innerHTML = `<button slot='action'>new action</button>`
-    assert_equals(toast.action.textContent, 'new action');
-}, 'changing the action button changes this.action');
-
-testToastElement((toast) => {
-    assert_equals(toast.action, null);
-}, 'the action property of a toast without an action is null');
-
-testToastElement((toast) => {
-    toast.innerHTML = `<button slot="action" id="first">first</button>
-        <button slot="action" id="second">second</button>`;
-
-    assert_equals(toast.action, toast.querySelector('#first'));
-}, 'toast action returns the first item with the action slot');
-
-test(() => {
-    const toast = showToast('Message', {action: 'action'});
-    const actionButton = toast.querySelector('button');
-
-    assertActionButtonOnToast(actionButton, toast);
-}, 'passing an action via showToast creates a button');
-
-test(() => {
-    const actionMarkup = '<b>strong text</b>';
-    const toast = showToast('Message', {action: actionMarkup});
-    const actionButton = toast.querySelector('button');
-
-    assert_equals(actionButton.textContent, actionMarkup);
-    assert_equals(toast.querySelector('b'), null);
-}, 'passing markup to the action option represents as text');
-
-test(() => {
-    const toast = document.createElement('std-toast');
-    toast.textContent = 'Message';
-    toast.show({action: 'action'});
-    const actionButton = toast.querySelector('button');
-
-    assert_equals(actionButton, null);
-}, 'passing action option to show does not create a button');
-
-test(() => {
-    const toast = showToast('Message', {action: null});
-    const actionButton = toast.querySelector('button');
-
-    assertActionButtonOnToast(actionButton, toast);
-    assert_equals(actionButton.textContent, 'null');
-}, 'passing non-string (null) as action option stringifies it and creates an action button');
-
-test(() => {
-    const toast = showToast('Message', {action: false});
-    const actionButton = toast.querySelector('button');
-
-    assertActionButtonOnToast(actionButton, toast);
-    assert_equals(actionButton.textContent, 'false');
-}, 'passing non-string (false) as action option stringifies it and creates an action button');
-
-test(() => {
-    const toast = showToast('Message', {action: 0});
-    const actionButton = toast.querySelector('button');
-
-    assertActionButtonOnToast(actionButton, toast);
-    assert_equals(actionButton.textContent, '0');
-}, 'passing non-string (0) as action option stringifies it and creates an action button');
-
-test(() => {
-    const toast = showToast('Message', {action: 1});
-    const actionButton = toast.querySelector('button');
-
-    assertActionButtonOnToast(actionButton, toast);
-    assert_equals(actionButton.textContent, '1');
-}, 'passing non-string (1) as action option stringifies it and creates an action button');
-
-test(() => {
-    const toast = showToast('Message', {action: {field: 'value'}});
-    const actionButton = toast.querySelector('button');
-
-    assertActionButtonOnToast(actionButton, toast);
-    assert_equals(actionButton.textContent, '[object Object]');
-}, 'passing non-string ({field: value}) as action option stringifies it and creates an action button');
-
-test(() => {
-    const toast = showToast('Message', {});
-    const actionButton = toast.querySelector('button');
-
-    assert_equals(actionButton, null);
-}, 'passing non-string (undefined) as action option does not create an action button');
-
-testToastElement((toast) => {
-    const actionButton = document.createElement('button');
-    actionButton.textContent = 'action';
-    toast.action = actionButton;
-
-    assertActionButtonOnToast(actionButton, toast);
-}, 'setting the action on an actionless toast inserts the element into the slot');
-
-testActionToast((toast, action) => {
-    const actionButton = document.createElement('button');
-    actionButton.textContent = 'replacement';
-    toast.action = actionButton;
-
-    assert_false(document.contains(action));
-    assertActionButtonOnToast(actionButton, toast);
-}, 'resetting the action on an action toast changes the action element');
-
-testToastElement((toast) => {
-    const text = document.createTextNode('some text');
-    assert_throws_js(TypeError, () => {
-        toast.action = text;
-    });
-}, 'setting the action to an invalid type (Text node) throws an error');
-
-testToastElement((toast) => {
-    const text = 'some text';
-    assert_throws_js(TypeError, () => {
-        toast.action = text;
-    });
-}, 'setting the action to an invalid type (string) throws an error');
-
-test(() => {
-    const actionButton = document.createElement('button');
-    actionButton.textContent = 'action';
-    const toast = showToast('Message', {action: actionButton});
-
-    assertActionButtonOnToast(actionButton, toast);
-}, 'showToast can take an Element as the action parameter');
-
-testActionToast((toast, action) => {
-    toast.action = null;
-
-    assert_not_equals(toast.action, action);
-    assert_equals(toast.querySelector('button'), null);
-}, 'setting toast.action to null removes the action from the toast');
-
-testActionToast((toast, action) => {
-    const wrongAction = document.createElement('button');
-    wrongAction.textContent = 'wrong';
-    wrongAction.setAttribute('slot', 'action');
-    toast.appendChild(wrongAction);
-
-    const correctAction = document.createElement('button');
-    correctAction.textContent = 'correct';
-    toast.action = correctAction;
-
-    assertActionButtonOnToast(correctAction, toast);
-}, 'resetting toast.action on a toast with multiple actions slotted sets properly');
-
-test(() => {
-    try {
-        Object.defineProperty(Element, Symbol.hasInstance, {
-            value: () => true,
-            configurable: true
-        });
-
-        const fakeElement = {};
-        const toast = showToast('Message');
-        assert_throws_js(TypeError, () => toast.action = fakeElement);
-    } finally {
-        delete Element[Symbol.hasInstance];
-    }
-}, 'spoofing element instance will not register as element to action setter');
-
-test(() => {
-    const iframe = document.createElement('iframe');
-    document.body.append(iframe);
-    iframe.contentDocument.body.innerHTML = '<div></div>';
-    const elementFromAnotherFrame = iframe.contentDocument.querySelector('div');
-
-    // Should not throw:
-    const toast = showToast('Message');
-    toast.action = elementFromAnotherFrame;
-}, 'element from iframe instance will pass correctly to action without throwing an error');
-</script>
diff --git a/tests/wpt/web-platform-tests/std-toast/attributes.html b/tests/wpt/web-platform-tests/std-toast/attributes.html
deleted file mode 100644
index 9b87280b668..00000000000
--- a/tests/wpt/web-platform-tests/std-toast/attributes.html
+++ /dev/null
@@ -1,127 +0,0 @@
-<!DOCTYPE html>
-<meta charset="utf-8">
-<title>Toast: attribute tests</title>
-
-<script src="/resources/testharness.js"></script>
-<script src="/resources/testharnessreport.js"></script>
-
-<main></main>
-
-<script type="module">
-import { testToastElement, assertToastShown, assertToastNotShown, testToastElementAsync } from './resources/helpers.js';
-
-testToastElement((toast) => {
-    toast.setAttribute('open', '');
-    assertToastShown(toast);
-}, 'setting `open` on a hidden toast shows the toast');
-
-testToastElement((toast) => {
-    toast.setAttribute('open', false);
-    assertToastShown(toast);
-}, 'setting `open` to false on a hidden toast shows the toast, because of string conversion');
-
-testToastElement((toast) => {
-    toast.show();
-    toast.setAttribute('open', 'test');
-    assertToastShown(toast);
-}, 'setting `open` on a shown toast does nothing');
-
-testToastElement((toast) => {
-    toast.show();
-    toast.setAttribute('open', 'test');
-    toast.setAttribute('open', 'test');
-    assertToastShown(toast);
-}, 'resetting `open` on a shown toast does nothing');
-
-testToastElement((toast) => {
-    toast.show();
-    toast.setAttribute('open', false);
-    assertToastShown(toast);
-}, 'setting `open` to false on a shown toast does nothing, because of string conversion');
-
-testToastElement((toast) => {
-    toast.show();
-    toast.removeAttribute('open');
-    assertToastNotShown(toast);
-}, 'removing `open` hides the toast');
-
-testToastElement((toast) => {
-    toast.show();
-    assert_true(toast.hasAttribute('open'));
-}, 'showing the toast adds open attribute');
-
-testToastElement((toast) => {
-    toast.show();
-    toast.hide();
-    assert_false(toast.hasAttribute('open'));
-}, 'hiding the toast removes open attribute');
-
-testToastElement((toast) => {
-    toast.toggleAttribute('open');
-    assert_true(toast.hasAttribute('open'));
-}, 'toggling `open` on a hidden toast sets the open attribute');
-
-testToastElement((toast) => {
-    toast.toggleAttribute('open');
-    toast.toggleAttribute('open');
-    assert_false(toast.hasAttribute('open'));
-}, 'toggling `open` twice leaves the toast with no open attribute');
-
-testToastElement((toast) => {
-    assert_false(toast.open);
-}, 'the `toast.open` boolean is false for a hidden toast');
-
-testToastElement((toast) => {
-    toast.show();
-    assert_true(toast.open);
-}, 'the `toast.open` boolean is true for a shown toast');
-
-testToastElement((toast) => {
-    toast.open = true;
-    assertToastShown(toast);
-    assert_equals(toast.getAttribute('open'), '');
-}, 'setting `toast.open` to true on a hidden toast will show the toast');
-
-testToastElement((toast) => {
-    toast.show();
-    toast.open = false;
-    assertToastNotShown(toast);
-}, 'setting `toast.open` to false on a shown toast will hide the toast');
-
-testToastElement((toast) => {
-    toast.open = 'truthy!';
-    assertToastShown(toast);
-    assert_equals(toast.getAttribute('open'), '');
-}, 'setting `toast.open` to some truthy value on a hidden toast will show the toast');
-
-testToastElement((toast) => {
-    toast.show();
-    toast.open = '';
-    assertToastNotShown(toast);
-}, 'setting `toast.open` to some falsy value on a shown toast will hide the toast');
-
-testToastElementAsync((t, toast) => {
-    toast.toggleAttribute('open', true);
-
-    t.step_timeout(() => {
-        assertToastShown(toast);
-        t.done();
-    }, 2000);
-}, 'toggling open attribute does not start timeout');
-
-testToastElement((toast) => {
-    const permitted_properties = ['constructor', 'show', 'hide', 'toggle', 'open', 'action', 'closeButton', 'type'];
-    assert_array_equals(permitted_properties.sort(), Object.getOwnPropertyNames(toast.__proto__).sort());
-}, 'toast only exposes certain properties');
-
-testToastElement((toast) => {
-    assert_false(toast.hasAttribute('type'));
-    assert_equals(toast.type, '');
-}, 'default type is empty string without attribute present');
-
-testToastElement((toast) => {
-    toast.type = 'info';
-    assert_equals(toast.type, '');
-    assert_equals(toast.getAttribute('type'), 'info');
-}, 'info was briefly a valid type, but no longer is, so it will return empty string');
-</script>
diff --git a/tests/wpt/web-platform-tests/std-toast/closebutton.html b/tests/wpt/web-platform-tests/std-toast/closebutton.html
deleted file mode 100644
index d53c78aca5d..00000000000
--- a/tests/wpt/web-platform-tests/std-toast/closebutton.html
+++ /dev/null
@@ -1,124 +0,0 @@
-<!DOCTYPE html>
-<meta charset="utf-8">
-<title>Toast: closebutton tests</title>
-
-<script src="/resources/testharness.js"></script>
-<script src="/resources/testharnessreport.js"></script>
-
-<main></main>
-
-<script type="module">
-import { showToast } from 'std:elements/toast';
-import { testToastElement } from './resources/helpers.js';
-
-testToastElement((toast) => {
-    toast.setAttribute('closebutton', '');
-
-    assert_true(toast.closeButton);
-}, 'the closeButton property returns true with an empty attribute');
-
-testToastElement((toast) => {
-    toast.setAttribute('closebutton', 'dismiss');
-
-    assert_equals(toast.closeButton, 'dismiss');
-}, 'the closeButton property returns the set attribute value');
-
-testToastElement((toast) => {
-    assert_false(toast.closeButton);
-}, 'the closeButton property returns false with no attribute');
-
-testToastElement((toast) => {
-    toast.setAttribute('closebutton', '');
-    assert_true(toast.closeButton);
-
-    toast.setAttribute('closebutton', 'dismiss');
-    assert_equals(toast.closeButton, 'dismiss');
-
-    toast.removeAttribute('closebutton');
-    assert_false(toast.closeButton);
-}, 'the closeButton property changes when the attribute changes');
-
-testToastElement((toast) => {
-    toast.closeButton = 'dismiss';
-
-    assert_equals(toast.getAttribute('closebutton'), 'dismiss');
-}, 'setting the closeButton property to any string changes the attribute to that string');
-
-testToastElement((toast) => {
-    toast.closeButton = '';
-
-    assert_equals(toast.getAttribute('closebutton'), '');
-}, 'setting the closeButton property to empty string changes the attribute to empty string');
-
-testToastElement((toast) => {
-    toast.closeButton = true;
-
-    assert_equals(toast.getAttribute('closebutton'), '');
-}, 'setting the closeButton property to true changes the attribute to empty string');
-
-testToastElement((toast) => {
-    toast.closeButton = false;
-
-    assert_false(toast.hasAttribute('closebutton'));
-}, 'setting the closeButton property to false removes the attribute');
-
-testToastElement((toast) => {
-    toast.closeButton = undefined;
-
-    assert_equals(toast.getAttribute('closebutton'), 'undefined');
-}, 'setting the closeButton property to undefined stringifies and sets to that');
-
-testToastElement((toast) => {
-    toast.closeButton = null;
-
-    assert_equals(toast.getAttribute('closebutton'), 'null');
-}, 'setting the closeButton property to null stringifies and sets to that');
-
-testToastElement((toast) => {
-    toast.closeButton = {};
-
-    assert_equals(toast.getAttribute('closebutton'), '[object Object]');
-}, 'setting the closeButton property to {} stringifies and sets to [object Object]');
-
-test(() => {
-    const toast = showToast('Message', { closeButton: true });
-
-    assert_equals(toast.getAttribute('closebutton'), '');
-}, 'setting the showToast closeButton option to true sets the closebutton attribute to empty string');
-
-test(() => {
-    const toast = showToast('Message', { closeButton: 'dismiss' });
-
-    assert_equals(toast.getAttribute('closebutton'), 'dismiss');
-}, 'setting the showToast closeButton option to some string sets that string as the closebutton attribute');
-
-test(() => {
-    const toast = showToast('Message', { closeButton: '' });
-
-    assert_equals(toast.getAttribute('closebutton'), '');
-}, 'setting the showToast closeButton option to empty string sets the closebutton attribute to empty string');
-
-test(() => {
-    const toast = showToast('Message', { closeButton: {} });
-
-    assert_equals(toast.getAttribute('closebutton'), '[object Object]');
-}, 'setting the showToast closeButton option to {} sets the closebutton attribute to [object Object]');
-
-test(() => {
-    const toast = showToast('Message', { closeButton: document.createElement('span') });
-
-    assert_equals(toast.getAttribute('closebutton'), '[object HTMLSpanElement]');
-}, 'passing an HTML element into the closeButton option of showToast stringifies and sets it to the closebutton attribute');
-
-test(() => {
-    const toast = showToast('Message', { closeButton: false });
-
-    assert_false(toast.hasAttribute('closebutton'));
-}, 'setting the showToast closeButton option to false does not put a close button on the toast');
-
-test(() => {
-    const toast = showToast('Message');
-
-    assert_false(toast.hasAttribute('closebutton'));
-}, 'calling showToast without the closeButton option does not put a closebutton on the toast');
-</script>
diff --git a/tests/wpt/web-platform-tests/std-toast/events-open.html b/tests/wpt/web-platform-tests/std-toast/events-open.html
deleted file mode 100644
index a49414d2fce..00000000000
--- a/tests/wpt/web-platform-tests/std-toast/events-open.html
+++ /dev/null
@@ -1,71 +0,0 @@
-<!DOCTYPE html>
-<meta charset="utf-8">
-<title>Toast: event (open) tests</title>
-
-<script src="/resources/testharness.js"></script>
-<script src="/resources/testharnessreport.js"></script>
-
-<main></main>
-
-<script type="module">
-import { testToastElement, EventCollector } from './resources/helpers.js';
-
-testToastElement((toast) => {
-    const counter = new EventCollector();
-
-    toast.addEventListener('show', counter.getCallback());
-    toast.open = true;
-
-    assert_equals(counter.getCount(), 1);
-}, 'setting open to true on a hidden toast triggers the `show` event');
-
-testToastElement((toast) => {
-    const counter = new EventCollector();
-
-    toast.open = true;
-    toast.addEventListener('show', counter.getCallback());
-    toast.open = true;
-
-    assert_equals(counter.getCount(), 0);
-}, 'setting open to true on a shown toast does not trigger the `show` event');
-
-testToastElement((toast) => {
-    const counter = new EventCollector();
-
-    toast.addEventListener('hide', counter.getCallback());
-    toast.open = false;
-
-    assert_equals(counter.getCount(), 0);
-}, 'setting open to false on a hidden toast does not trigger the `hide` event');
-
-testToastElement((toast) => {
-    const counter = new EventCollector();
-
-    toast.show();
-    toast.addEventListener('hide', counter.getCallback());
-    toast.open = false;
-
-    assert_equals(counter.getCount(), 1);
-}, 'setting open to false on a shown toast triggers the `hide` event');
-
-testToastElement((toast) => {
-    const counter = new EventCollector();
-
-    toast.addEventListener('show', counter.getCallback());
-    toast.open = true;
-    toast.open = true;
-
-    assert_equals(counter.getCount(), 1);
-}, 'setting open to true twice only triggers the `show` event once');
-
-testToastElement((toast) => {
-    const counter = new EventCollector();
-
-    toast.show();
-    toast.addEventListener('hide', counter.getCallback());
-    toast.open = false;
-    toast.open = false;
-
-    assert_equals(counter.getCount(), 1);
-}, 'setting open to false twice only triggers the `hide` event once');
-</script>
diff --git a/tests/wpt/web-platform-tests/std-toast/events-showhide.html b/tests/wpt/web-platform-tests/std-toast/events-showhide.html
deleted file mode 100644
index 547f742f713..00000000000
--- a/tests/wpt/web-platform-tests/std-toast/events-showhide.html
+++ /dev/null
@@ -1,98 +0,0 @@
-<!DOCTYPE html>
-<meta charset="utf-8">
-<title>Toast: event (show/hide) tests</title>
-
-<script src="/resources/testharness.js"></script>
-<script src="/resources/testharnessreport.js"></script>
-
-<main></main>
-
-<script type="module">
-import { testToastElement, EventCollector } from './resources/helpers.js';
-
-testToastElement((toast) => {
-    const counter = new EventCollector();
-
-    toast.addEventListener('show', counter.getCallback());
-    toast.show();
-
-    assert_equals(counter.getCount(), 1);
-}, 'calling `show()` on a hidden toast triggers the `show` event');
-
-testToastElement((toast) => {
-    const counter = new EventCollector();
-
-    toast.show();
-    toast.addEventListener('show', counter.getCallback());
-    toast.show();
-
-    assert_equals(counter.getCount(), 0);
-}, 'calling `show()` on a shown toast does not trigger the `show` event');
-
-testToastElement((toast) => {
-    const counter = new EventCollector();
-
-    toast.addEventListener('hide', counter.getCallback());
-    toast.hide();
-
-    assert_equals(counter.getCount(), 0);
-}, 'calling `hide()` on a hidden toast does not trigger the `hide` event');
-
-testToastElement((toast) => {
-    const counter = new EventCollector();
-
-    toast.show();
-    toast.addEventListener('hide', counter.getCallback());
-    toast.hide();
-
-    assert_equals(counter.getCount(), 1);
-}, 'calling `hide()` on a shown toast triggers the `hide` event');
-
-testToastElement((toast) => {
-    const counter = new EventCollector();
-
-    toast.addEventListener('show', counter.getCallback());
-    toast.show();
-    toast.show();
-
-    assert_equals(counter.getCount(), 1);
-}, 'calling `show()` twice only triggers the `show` event once');
-
-testToastElement((toast) => {
-    const counter = new EventCollector();
-
-    toast.show();
-    toast.addEventListener('hide', counter.getCallback());
-    toast.hide();
-    toast.hide();
-
-    assert_equals(counter.getCount(), 1);
-}, 'calling `hide()` twice only triggers the `hide` event once');
-
-testToastElement((toast) => {
-    const events = new EventCollector();
-
-    toast.addEventListener('show', events.getCallback());
-
-    toast.show();
-    toast.hide();
-    toast.show();
-
-    assert_equals(events.getCount(), 2);
-    assert_not_equals(events.getEvents()[0], events.getEvents()[1]);
-}, "separate openings trigger different `show` events");
-
-testToastElement((toast) => {
-    const events = new EventCollector();
-
-    toast.addEventListener('hide', events.getCallback());
-
-    toast.show();
-    toast.hide();
-    toast.show();
-    toast.hide();
-
-    assert_equals(events.getCount(), 2);
-    assert_not_equals(events.getEvents()[0], events.getEvents()[1]);
-}, "separate closings trigger different `hide` events");
-</script>
diff --git a/tests/wpt/web-platform-tests/std-toast/methods.html b/tests/wpt/web-platform-tests/std-toast/methods.html
deleted file mode 100644
index 981b9fba434..00000000000
--- a/tests/wpt/web-platform-tests/std-toast/methods.html
+++ /dev/null
@@ -1,126 +0,0 @@
-<!DOCTYPE html>
-<meta charset="utf-8">
-<title>Toast: method tests</title>
-
-<script src="/resources/testharness.js"></script>
-<script src="/resources/testharnessreport.js"></script>
-
-<main></main>
-<div></div>
-
-<script type="module">
-import { testToastElement, assertToastShown, assertToastNotShown, testToastElementAsync } from './resources/helpers.js';
-
-testToastElement((toast) => {
-    toast.show();
-
-    assertToastShown(toast);
-}, 'calling `show()` on a hidden toast opens and displays it');
-
-testToastElement((toast) => {
-    toast.toggleAttribute('open');
-    toast.show();
-
-    assertToastShown(toast);
-}, 'calling `show()` on a shown toast does nothing');
-
-testToastElement((toast) => {
-    toast.toggleAttribute('open');
-    toast.hide();
-
-    assertToastNotShown(toast);
-}, 'calling `hide()` on a shown toast hides the toast');
-
-testToastElement((toast) => {
-    toast.hide();
-
-    assertToastNotShown(toast);
-}, 'calling `hide()` on a hidden toast does nothing');
-
-testToastElement((toast) => {
-    toast.toggle();
-
-    assertToastShown(toast);
-}, 'calling `toggle()` on a hidden toast shows the toast');
-
-testToastElement((toast) => {
-    toast.show();
-    toast.toggle();
-
-    assertToastNotShown(toast);
-}, 'calling `toggle()` on a shown toast hides the toast');
-
-testToastElement((toast) => {
-    toast.toggle(true);
-
-    assertToastShown(toast);
-}, 'calling `toggle()` with `force` parameter set to true on a hidden opens the toast');
-
-testToastElement((toast) => {
-    toast.show();
-    toast.toggle(true);
-
-    assertToastShown(toast);
-}, 'calling `toggle()` with `force` parameter set to true on a shown toast does not close the toast');
-
-testToastElement((toast) => {
-    toast.toggle(false);
-
-    assertToastNotShown(toast);
-}, 'calling `toggle()` with `force` parameter set to false on a hidden toast does not open the toast');
-
-testToastElement((toast) => {
-    toast.show();
-    toast.toggle(false);
-
-    assertToastNotShown(toast);
-}, 'calling `toggle()` with `force` parameter set to false on a shown toast closes the toast');
-
-testToastElementAsync((t, toast) => {
-    toast.show({duration: 50});
-
-    // time = 49
-    t.step_timeout(() => {
-        assertToastShown(toast);
-        toast.show({duration: 50});
-
-        // time = 98
-        t.step_timeout(() => {
-            assertToastShown(toast);
-
-            // time = 99
-            t.step_timeout(() => {
-                assertToastNotShown(toast);
-                t.done();
-            }, 1000);
-        }, 49);
-    }, 49);
-}, 'calling `show()` twice resets the timeout');
-
-testToastElementAsync((t, toast) => {
-    toast.show({duration: 50});
-
-    // time = 48
-    t.step_timeout(() => {
-        assertToastShown(toast);
-        toast.hide();
-
-        // time = 49
-        t.step_timeout(() => {
-            assertToastNotShown(toast);
-
-            // time = 50
-            t.step_timeout(() => {
-                toast.show({duration: 2});
-
-                // time = 51
-                t.step_timeout(() => {
-                    assertToastShown(toast);
-                    toast.hide();
-                    t.done();
-                }, 1);
-            }, 1);
-        }, 1);
-    }, 48);
-}, 'calling `hide()` clears the timeout');
-</script>
diff --git a/tests/wpt/web-platform-tests/std-toast/options.html b/tests/wpt/web-platform-tests/std-toast/options.html
deleted file mode 100644
index 0383d71f9ae..00000000000
--- a/tests/wpt/web-platform-tests/std-toast/options.html
+++ /dev/null
@@ -1,129 +0,0 @@
-<!DOCTYPE html>
-<meta charset="utf-8">
-<meta name="timeout" content="long">
-<title>Toast: option tests</title>
-
-<script src="/resources/testharness.js"></script>
-<script src="/resources/testharnessreport.js"></script>
-
-<body>
-</body>
-
-<script type="module">
-import { showToast, StdToastElement } from 'std:elements/toast';
-import { assertToastNotShown, assertToastShown } from './resources/helpers.js';
-
-// message
-test(() => {
-    const toast =  new StdToastElement('test');
-    document.body.appendChild(toast);
-
-    assert_equals(toast.textContent, 'test');
-}, 'passing test string as message sets the message properly');
-
-test(() => {
-    const toast = new StdToastElement('<p>rich text</p>');
-    document.body.appendChild(toast);
-
-    assert_equals(toast.textContent, '<p>rich text</p>');
-    assert_equals(toast.querySelector('p'), null);
-}, 'passing markup to the constructor does not pass through the markup behaviors');
-
-test(() => {
-    const toast =  new StdToastElement(false);
-    document.body.appendChild(toast);
-
-    assert_equals(toast.textContent, 'false');
-}), 'passing false as message converts to the string `false`';
-
-test(() => {
-    const toast =  new StdToastElement();
-    document.body.appendChild(toast);
-
-    assert_equals(toast.textContent, '');
-}, 'passing nothing as message sets the message to the empty string');
-
-test(() => {
-    const toast =  new StdToastElement(undefined);
-    document.body.appendChild(toast);
-
-    assert_equals(toast.textContent, '');
-}, 'passing `undefined` as message sets the message to the empty string');
-
-test(() => {
-    const toast =  new StdToastElement('');
-    document.body.appendChild(toast);
-
-    assert_equals(toast.textContent, '');
-}, 'passing empty string as message sets the message to the empty string');
-
-test(() => {
-    const toastString = '<std-toast id="test">test</std-toast>';
-    document.body.innerHTML = toastString;
-    const toast = document.body.querySelector('#test');
-
-    assert_equals(toast.textContent, 'test');
-}, 'HTML created toast has `test` as its text content');
-
-// duration
-async_test(t => {
-    const toast = showToast('message');
-
-    t.step_timeout(() => {
-        assertToastShown(toast);
-    }, 2999);
-
-    t.step_timeout(() => {
-        assertToastNotShown(toast);
-        t.done();
-    }, 3000);
-
-    t.add_cleanup(function() {
-        toast.remove();
-    });
-}, 'showToast closes after default duration of 3000ms');
-// FIXME: find a way to virtualize time instead of waiting 3000ms
-// BUG: https://github.com/web-platform-tests/wpt/issues/17489
-
-async_test(t => {
-    const toast = showToast('message', {duration: 50});
-
-    t.step_timeout(() => {
-        assertToastShown(toast);
-    }, 49);
-
-    t.step_timeout(() => {
-        assertToastNotShown(toast);
-        t.done();
-    }, 50);
-
-    t.add_cleanup(function() {
-        toast.remove();
-    });
-}, 'showToast closes after user specified 50ms');
-
-async_test(t => {
-    const toast = showToast('message', {duration: Infinity});
-
-    t.step_timeout(() => {
-        assertToastShown(toast);
-        t.done();
-    }, 50);
-
-    t.add_cleanup(function() {
-        toast.remove();
-    });
-}, 'passing Infinity as the duration leaves the toast open for at least 50ms');
-
-test(() => {
-    assert_throws_js(RangeError, () => {
-        const toast = showToast('Message', {duration: 0});
-    });
-}, 'setting the duration to 0 throws a RangeError');
-
-test(() => {
-    assert_throws_js(RangeError, () => {
-        const toast = showToast('Message', {duration: -5});
-    });
-}, 'setting the duration to a negative number throws a RangeError');
-</script>
diff --git a/tests/wpt/web-platform-tests/std-toast/ref-tests/toast-slotting-expected.html b/tests/wpt/web-platform-tests/std-toast/ref-tests/toast-slotting-expected.html
deleted file mode 100644
index b4b365c7a9d..00000000000
--- a/tests/wpt/web-platform-tests/std-toast/ref-tests/toast-slotting-expected.html
+++ /dev/null
@@ -1,8 +0,0 @@
-<!DOCTYPE html>
-<meta charset="utf-8">
-<title>Toast: slotting test reference</title>
-<script type="module">
-import 'std:elements/toast';
-</script>
-<p>Pass if the toast is displayed with the action button last.</p>
-<std-toast open>First. Second. <button>Last.</button></std-toast>
diff --git a/tests/wpt/web-platform-tests/std-toast/ref-tests/toast-slotting.html b/tests/wpt/web-platform-tests/std-toast/ref-tests/toast-slotting.html
deleted file mode 100644
index 4d6f5038f2d..00000000000
--- a/tests/wpt/web-platform-tests/std-toast/ref-tests/toast-slotting.html
+++ /dev/null
@@ -1,11 +0,0 @@
-<!DOCTYPE html>
-<meta charset="utf-8">
-<title>Toast: slotting test</title>
-<link rel="help" href="https://github.com/jackbsteinberg/std-toast">
-<meta name="assert" content="Toast slots action button behind any text">
-<link rel="match" href="toast-slotting-expected.html">
-<script type="module">
-import 'std:elements/toast';
-</script>
-<p>Pass if the toast is displayed with the action button last.</p>
-<std-toast open>First. <button slot="action">Last.</button> Second. </std-toast>
\ No newline at end of file
diff --git a/tests/wpt/web-platform-tests/std-toast/reflection.html b/tests/wpt/web-platform-tests/std-toast/reflection.html
deleted file mode 100644
index 36cbaf65228..00000000000
--- a/tests/wpt/web-platform-tests/std-toast/reflection.html
+++ /dev/null
@@ -1,24 +0,0 @@
-<!doctype html>
-<title>HTML5 reflection tests:  std-toast</title>
-<meta name=timeout content=long>
-
-<div id=log></div>
-
-<script src="/resources/testharness.js"></script>
-<script src="/resources/testharnessreport.js"></script>
-<script src="/html/dom/original-harness.js"></script>
-<script src="/html/dom/new-harness.js"></script>
-
-<script type="module">
-import 'std:elements/toast';
-
-const toastElement = {
-    'std-toast': {
-        open: 'boolean',
-        type: {type: 'enum', keywords: ['success', 'error', 'warning']},
-    },
-};
-
-mergeElements(toastElement);
-</script>
-<script src="/html/dom/reflection.js" defer></script>
diff --git a/tests/wpt/web-platform-tests/std-toast/resources/helpers.js b/tests/wpt/web-platform-tests/std-toast/resources/helpers.js
deleted file mode 100644
index 256f0c88040..00000000000
--- a/tests/wpt/web-platform-tests/std-toast/resources/helpers.js
+++ /dev/null
@@ -1,101 +0,0 @@
-import { showToast, StdToastElement } from 'std:elements/toast';
-
-// helper functions to keep tests from bleeding into each other
-
-const runTest = (testFn, name, toast, action) => {
-    try {
-        test(() => {
-            testFn(toast, action);
-        }, name);
-    } finally {
-        toast.remove();
-    }
-};
-
-const runTestAsync = (testFn, name, toast) => {
-    async_test(t => {
-        testFn(t, toast);
-        t.add_cleanup(() => {
-            toast.remove();
-        });
-    }, name);
-};
-
-export const testToastElement = (testFn, name) => {
-    const toast = new StdToastElement('Message', {});
-    document.querySelector('main').appendChild(toast);
-
-    runTest(testFn, name, toast);
-};
-
-export const testToastElementAsync = (testFn, name) => {
-    const toast = new StdToastElement('Message', {});
-    document.querySelector('main').appendChild(toast);
-
-    runTestAsync(testFn, name, toast);
-};
-
-export const testShowToast = (testFn, name) => {
-    const toast = showToast("message");
-
-    runTest(testFn, name, toast);
-};
-
-export const testActionToast = (testFn, name) => {
-    const toast = new StdToastElement('Message', {});
-    const action = document.createElement('button');
-    action.setAttribute('slot', 'action');
-    action.textContent = 'action';
-    toast.appendChild(action);
-    document.querySelector('main').appendChild(toast);
-
-    runTest(testFn, name, toast, action);
-};
-
-export const assertToastShown = (toast) => {
-    assert_not_equals(window.getComputedStyle(toast).display, 'none');
-    assert_true(toast.hasAttribute('open'));
-    assert_true(toast.open);
-};
-
-export const assertToastNotShown = (toast) => {
-    assert_equals(window.getComputedStyle(toast).display, 'none');
-    assert_false(toast.hasAttribute('open'));
-    assert_false(toast.open);
-};
-
-export const assertActionButtonOnToast = (action, toast) => {
-    assert_equals(toast.action, action);
-    assert_equals(action.getAttribute('slot'), 'action');
-    assert_equals(action, toast.querySelector('button'));
-};
-
-export const assertComputedStyleMapsEqual = (element1, element2) => {
-    assert_greater_than(element1.computedStyleMap().size, 0);
-    for (const [styleProperty, baseStyleValues] of element1.computedStyleMap()) {
-        const refStyleValues = element2.computedStyleMap().getAll(styleProperty);
-        assert_equals(baseStyleValues.length, refStyleValues.length, `${styleProperty} length`);
-
-        for (let i = 0; i < baseStyleValues.length; ++i) {
-            const baseStyleValue = baseStyleValues[i];
-            const refStyleValue = refStyleValues[i];
-            assert_equals(baseStyleValue.toString(), refStyleValue.toString(), `diff at value ${styleProperty}`);
-        }
-    }
-}
-
-export class EventCollector {
-    events = [];
-
-    getCallback() {
-        return (e) => {this.events.push(e)};
-    }
-
-    getCount() {
-        return this.events.length;
-    }
-
-    getEvents() {
-        return this.events;
-    }
-}
diff --git a/tests/wpt/web-platform-tests/std-toast/show-toast.html b/tests/wpt/web-platform-tests/std-toast/show-toast.html
deleted file mode 100644
index 50cdc2c06dd..00000000000
--- a/tests/wpt/web-platform-tests/std-toast/show-toast.html
+++ /dev/null
@@ -1,63 +0,0 @@
-<!DOCTYPE html>
-<meta charset="utf-8">
-<title>Toast: showToast tests</title>
-
-<script src="/resources/testharness.js"></script>
-<script src="/resources/testharnessreport.js"></script>
-
-<body>
-</body>
-
-<script type="module">
-import { showToast, StdToastElement } from 'std:elements/toast';
-import { testShowToast, assertToastNotShown, assertToastShown } from './resources/helpers.js';
-
-testShowToast((toast) => {
-    assert_true(toast != null);
-    assert_true(toast instanceof StdToastElement);
-}, 'showToast creates and returns a toast');
-
-testShowToast((toast) => {
-    assert_true(document.querySelector('std-toast') === toast);
-}, 'showToast puts the toast in the DOM');
-
-testShowToast((toast) => {
-    assertToastShown(toast);
-}, 'showToast displays the toast by default');
-
-testShowToast((toast) => {
-    toast.hide();
-
-    assertToastNotShown(toast);
-}, 'hiding showToast immediately does not display it');
-
-testShowToast((toast) => {
-    toast.show();
-
-    assertToastShown(toast);
-}, 'calling show after showToast does nothing');
-
-testShowToast((toast) => {
-    let toast2;
-    try {
-        toast2 = showToast('message2');
-
-        assert_not_equals(toast, toast2);
-    }
-    finally {
-        toast2.remove();
-    }
-}, 'calling showToast multiple times creates multiple different toasts');
-
-test(() => {
-    const toast = showToast('test');
-    assert_equals(toast.textContent, 'test');
-}, 'showToast created toast has `test` as its text content');
-
-test(() => {
-    const toast = showToast('<p>rich text</p>');
-
-    assert_equals(toast.textContent, '<p>rich text</p>');
-    assert_equals(toast.querySelector('p'), null);
-}, 'passing markup to showToast does not pass through the markup behaviors');
-</script>
diff --git a/tests/wpt/web-platform-tests/std-toast/styles.html b/tests/wpt/web-platform-tests/std-toast/styles.html
deleted file mode 100644
index 1db8620485d..00000000000
--- a/tests/wpt/web-platform-tests/std-toast/styles.html
+++ /dev/null
@@ -1,100 +0,0 @@
-<!DOCTYPE html>
-<meta charset="utf-8">
-<title>Toast: style tests</title>
-
-<script src="/resources/testharness.js"></script>
-<script src="/resources/testharnessreport.js"></script>
-
-<main>
-</main>
-
-<script type="module">
-import { testToastElement, assertComputedStyleMapsEqual } from './resources/helpers.js';
-
-testToastElement((toast) => {
-    toast.open = true;
-
-    const mockToast = document.createElement('span');
-    mockToast.id = 'mock-toast-open';
-    mockToast.textContent = 'Message';
-
-    const mockStyler = document.createElement('style');
-    mockStyler.textContent = `
-        #mock-toast-open {
-          position: fixed;
-          bottom: 1em;
-          right: 1em;
-          border: solid;
-          padding: 1em;
-          background: white;
-          color: black;
-          z-index: 1;
-        }`;
-
-    document.querySelector('main').appendChild(mockStyler);
-    document.querySelector('main').appendChild(mockToast);
-
-    assertComputedStyleMapsEqual(toast, mockToast);
-}, 'the computed style map of an open unstyled toast is the same as a span given toast defaults');
-
-testToastElement((toast) => {
-    const mockToast = document.createElement('span');
-    mockToast.id = 'mock-toast-hidden';
-    mockToast.textContent = 'Message';
-
-    const mockStyler = document.createElement('style');
-    mockStyler.textContent = `
-        #mock-toast-hidden {
-          position: fixed;
-          bottom: 1em;
-          right: 1em;
-          border: solid;
-          padding: 1em;
-          background: white;
-          color: black;
-          z-index: 1;
-          display: none;
-        }`;
-
-    document.querySelector('main').appendChild(mockStyler);
-    document.querySelector('main').appendChild(mockToast);
-
-    assertComputedStyleMapsEqual(toast, mockToast);
-}, 'the computed style map of a closed unstyled toast is the same as a span given toast defaults');
-
-testToastElement((toast) => {
-  toast.type = 'error';
-
-  const styles = window.getComputedStyle(toast);
-  assert_equals(styles.borderColor, 'rgb(255, 0, 0)');
-}, 'changing type to error changes the border color to red');
-
-testToastElement((toast) => {
-  toast.type = 'warning';
-
-  const styles = window.getComputedStyle(toast);
-  assert_equals(styles.borderColor, 'rgb(255, 165, 0)');
-}, 'changing type to warning changes the border color to orange');
-
-testToastElement((toast) => {
-  toast.type = 'success';
-
-  const styles = window.getComputedStyle(toast);
-  assert_equals(styles.borderColor, 'rgb(0, 128, 0)');
-}, 'changing type to success changes the border color to green');
-
-testToastElement((toast) => {
-  const styler = document.createElement('style');
-  styler.append(`
-    [type=error i] {
-      border-color: pink;
-    }
-  `);
-  document.querySelector('main').appendChild(styler);
-
-  toast.type = 'error';
-
-  const styles = window.getComputedStyle(toast);
-  assert_equals(styles.borderColor, 'rgb(255, 192, 203)');
-}, 'outside styles can set type styles');
-</script>
diff --git a/tests/wpt/web-platform-tests/webrtc/RTCDTMFSender-insertDTMF.https.html b/tests/wpt/web-platform-tests/webrtc/RTCDTMFSender-insertDTMF.https.html
index ac27c5139cc..71cfe70171f 100644
--- a/tests/wpt/web-platform-tests/webrtc/RTCDTMFSender-insertDTMF.https.html
+++ b/tests/wpt/web-platform-tests/webrtc/RTCDTMFSender-insertDTMF.https.html
@@ -53,17 +53,15 @@
       All other characters (and only those other characters) MUST be considered
       unrecognized.
    */
-  promise_test(t => {
-    return createDtmfSender()
-  .then(dtmfSender => {
-      dtmfSender.insertDTMF('');
-      dtmfSender.insertDTMF('012345689');
-      dtmfSender.insertDTMF('ABCD');
-      dtmfSender.insertDTMF('abcd');
-      dtmfSender.insertDTMF('#*');
-      dtmfSender.insertDTMF(',');
-      dtmfSender.insertDTMF('0123456789ABCDabcd#*,');
-    });
+  promise_test(async t => {
+    const dtmfSender = await createDtmfSender();
+    dtmfSender.insertDTMF('');
+    dtmfSender.insertDTMF('012345689');
+    dtmfSender.insertDTMF('ABCD');
+    dtmfSender.insertDTMF('abcd');
+    dtmfSender.insertDTMF('#*');
+    dtmfSender.insertDTMF(',');
+    dtmfSender.insertDTMF('0123456789ABCDabcd#*,');
   }, 'insertDTMF() should succeed if tones contains valid DTMF characters');
 
 
@@ -72,21 +70,19 @@
       6.  If tones contains any unrecognized characters, throw an
           InvalidCharacterError.
    */
-  promise_test(t => {
-    return createDtmfSender()
-    .then(dtmfSender => {
-      assert_throws_dom('InvalidCharacterError', () =>
-        // 'F' is invalid
-        dtmfSender.insertDTMF('123FFABC'));
+  promise_test(async t => {
+    const dtmfSender = await createDtmfSender();
+    assert_throws_dom('InvalidCharacterError', () =>
+      // 'F' is invalid
+      dtmfSender.insertDTMF('123FFABC'));
 
-      assert_throws_dom('InvalidCharacterError', () =>
-        // 'E' is invalid
-        dtmfSender.insertDTMF('E'));
+    assert_throws_dom('InvalidCharacterError', () =>
+      // 'E' is invalid
+      dtmfSender.insertDTMF('E'));
 
-      assert_throws_dom('InvalidCharacterError', () =>
-        // ' ' is invalid
-        dtmfSender.insertDTMF('# *'));
-    });
+    assert_throws_dom('InvalidCharacterError', () =>
+      // ' ' is invalid
+      dtmfSender.insertDTMF('# *'));
   }, 'insertDTMF() should throw InvalidCharacterError if tones contains invalid DTMF characters');
 
   /*
@@ -152,37 +148,29 @@
 
       7.  Set the object's toneBuffer attribute to tones.
    */
-  promise_test(t => {
-    return createDtmfSender()
-    .then(dtmfSender => {
-      dtmfSender.insertDTMF('123');
-      assert_equals(dtmfSender.toneBuffer, '123');
+  promise_test(async t => {
+    const dtmfSender = await createDtmfSender();
+    dtmfSender.insertDTMF('123');
+    assert_equals(dtmfSender.toneBuffer, '123');
 
-      dtmfSender.insertDTMF('ABC');
-      assert_equals(dtmfSender.toneBuffer, 'ABC');
+    dtmfSender.insertDTMF('ABC');
+    assert_equals(dtmfSender.toneBuffer, 'ABC');
 
-      dtmfSender.insertDTMF('bcd');
-      assert_equals(dtmfSender.toneBuffer, 'BCD');
-    });
+    dtmfSender.insertDTMF('bcd');
+    assert_equals(dtmfSender.toneBuffer, 'BCD');
   }, 'insertDTMF() should set toneBuffer to provided tones normalized, with old tones overridden');
 
-  promise_test(t => {
-    let dtmfSender;
-    let sender;
-    let pc = new RTCPeerConnection();
+  promise_test(async t => {
+    const pc = new RTCPeerConnection();
     t.add_cleanup(() => pc.close());
-    return getTrackFromUserMedia('audio')
-      .then(([track, mediaStream]) => {
-        sender = pc.addTrack(track, mediaStream);
-        return pc.createOffer();
-      }).then(offer => {
-        pc.setLocalDescription(offer);
-        dtmfSender = sender.dtmf;
-        pc.removeTrack(sender);
-        pc.close();
-        assert_throws_dom('InvalidStateError', () =>
-                          dtmfSender.insertDTMF('123'));
-      });
+    const [track, mediaStream] = await getTrackFromUserMedia('audio');
+    const sender = pc.addTrack(track, mediaStream);
+    await pc.setLocalDescription(await pc.createOffer());
+    const dtmfSender = sender.dtmf;
+    pc.removeTrack(sender);
+    pc.close();
+    assert_throws_dom('InvalidStateError', () =>
+                      dtmfSender.insertDTMF('123'));
   }, 'insertDTMF() after remove and close should reject');
 
 </script>
diff --git a/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-operations.https.html b/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-operations.https.html
new file mode 100644
index 00000000000..e88c8b28172
--- /dev/null
+++ b/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-operations.https.html
@@ -0,0 +1,211 @@
+<!doctype html>
+<meta charset=utf-8>
+<title></title>
+<script src=/resources/testharness.js></script>
+<script src=/resources/testharnessreport.js></script>
+<script>
+'use strict';
+
+promise_test(async t => {
+  const pc1 = new RTCPeerConnection();
+  t.add_cleanup(() => pc1.close());
+  const pc2 = new RTCPeerConnection();
+  t.add_cleanup(() => pc2.close());
+
+  pc1.addTransceiver("video");
+  const offer = await pc1.createOffer();
+  await pc1.setLocalDescription(offer);
+  const {candidate} = await new Promise(r => pc1.onicecandidate = r);
+  try {
+    await pc2.addIceCandidate(candidate);
+    assert_unreached("Control. Must not succeed");
+  } catch (e) {
+    assert_equals(e.name, "InvalidStateError");
+  }
+  const p = pc2.setRemoteDescription(offer);
+  await pc2.addIceCandidate(candidate);
+  await p;
+}, "addIceCandidate chains onto SRD, fails before");
+
+promise_test(async t => {
+  const pc1 = new RTCPeerConnection();
+  t.add_cleanup(() => pc1.close());
+  const pc2 = new RTCPeerConnection();
+  t.add_cleanup(() => pc2.close());
+
+  pc1.addTransceiver("video");
+  await Promise.all([
+    pc1.createOffer(),
+    pc1.setLocalDescription({type: "offer"})
+  ]);
+  await Promise.all([
+    pc2.setRemoteDescription(pc1.localDescription),
+    pc2.createAnswer(),
+    pc2.setLocalDescription({type: "answer"})
+  ]);
+  await pc1.setRemoteDescription(pc2.localDescription);
+}, "Pack operations queue with implicit offer and answer");
+
+promise_test(async t => {
+  const pc1 = new RTCPeerConnection();
+  t.add_cleanup(() => pc1.close());
+  const pc2 = new RTCPeerConnection();
+  t.add_cleanup(() => pc2.close());
+
+  const state = (pc, s) => new Promise(r => pc.onsignalingstatechange =
+                                       () => pc.signalingState == s && r());
+  pc1.addTransceiver("video");
+  pc1.createOffer();
+  pc1.setLocalDescription({type: "offer"});
+  await state(pc1, "have-local-offer");
+  pc2.setRemoteDescription(pc1.localDescription);
+  pc2.createAnswer();
+  pc2.setLocalDescription({type: "answer"});
+  await state(pc2, "stable");
+  await pc1.setRemoteDescription(pc2.localDescription);
+}, "Negotiate solely by operations queue and signaling state");
+
+// Helpers to test APIs "return a promise rejected with a newly created" error.
+// Strictly speaking this means already-rejected upon return.
+function promiseState(p) {
+  const t = {};
+  return Promise.race([p, t])
+    .then(v => (v === t)? "pending" : "fulfilled", () => "rejected");
+}
+
+// However, to allow promises to be used in implementations, this helper adds
+// some slack: returning a pending promise will pass, provided it is rejected
+// before the end of the current run of the event loop (i.e. on microtask queue
+// before next task).
+async function promiseStateFinal(p) {
+  for (let i = 0; i < 20; i++) {
+    await promiseState(p);
+  }
+  return promiseState(p);
+}
+
+promise_test(async t => {
+  assert_equals(await promiseState(Promise.resolve()), "fulfilled");
+  assert_equals(await promiseState(Promise.reject()), "rejected");
+  assert_equals(await promiseState(new Promise(() => {})), "pending");
+}, "promiseState helper works");
+
+promise_test(async t => {
+  const pc = new RTCPeerConnection();
+  t.add_cleanup(() => pc.close());
+  const p = pc.setLocalDescription({type: "offer", sdp: "blah"});
+  const haveState = promiseStateFinal(p);
+  try {
+    await p;
+    assert_unreached("Control. Must not succeed");
+  } catch (e) {
+    assert_equals(e.name, "InvalidModificationError");
+  }
+  assert_equals(await haveState, "rejected", "promise rejected on same task");
+}, "Operations chain must run first operation's sync part synchronously");
+
+// Helper builds on above test to check if operations queue is empty or not.
+async function isOperationsChainEmpty(pc) {
+  const type = pc.signalingState == "have-remote-offer" ? "answer" : "offer";
+  const p = pc.setLocalDescription({type, sdp: "blah"});
+  const state = await promiseStateFinal(p);
+  try {
+    await p;
+    assert_unreached("Control. Must not succeed");
+  } catch (e) {
+    assert_equals(e.name, "InvalidModificationError", "isOperationsChainEmpty");
+  }
+  return state == "rejected";
+}
+
+promise_test(async t => {
+  const pc = new RTCPeerConnection();
+  t.add_cleanup(() => pc.close());
+  assert_true(await isOperationsChainEmpty(pc), "Empty to start");
+}, "isOperationsChainEmpty detects empty");
+
+promise_test(async t => {
+  const pc = new RTCPeerConnection();
+  t.add_cleanup(() => pc.close());
+  pc.createDataChannel("dummy");
+  const p = await pc.createOffer();
+  try {
+    await pc.setLocalDescription({type: "offer", sdp: "blah"});
+    assert_unreached("Control. Must not succeed");
+  } catch (e) {
+    assert_equals(e.name, "InvalidModificationError");
+  }
+}, "SLD(offer) must validate against LastCreatedOffer early (prerequisite)");
+
+promise_test(async t => {
+  const pc = new RTCPeerConnection();
+  t.add_cleanup(() => pc.close());
+  pc.createDataChannel("dummy");
+  await pc.setRemoteDescription(await pc.createOffer());
+  try {
+    await pc.setLocalDescription({type: "offer", sdp: "blah"});
+    assert_unreached("Control. Must not succeed");
+  } catch (e) {
+    assert_equals(e.name, "InvalidModificationError");
+  }
+}, "SLD(offer) must validate input before signaling state (prerequisite)");
+
+promise_test(async t => {
+  const pc = new RTCPeerConnection();
+  t.add_cleanup(() => pc.close());
+  pc.createDataChannel("dummy");
+  const p = pc.createOffer();
+  assert_true(!await isOperationsChainEmpty(pc), "Non-empty queue");
+  await p;
+}, "createOffer uses operations chain");
+
+promise_test(async t => {
+  const pc = new RTCPeerConnection();
+  t.add_cleanup(() => pc.close());
+  pc.createDataChannel("dummy");
+  await pc.setRemoteDescription(await pc.createOffer());
+  const p = pc.createAnswer();
+  assert_true(!await isOperationsChainEmpty(pc), "Non-empty queue");
+  await p;
+}, "createAnswer uses operations chain");
+
+promise_test(async t => {
+  const pc = new RTCPeerConnection();
+  t.add_cleanup(() => pc.close());
+  pc.createDataChannel("dummy");
+
+  const offer = await pc.createOffer();
+  const p = pc.setLocalDescription(offer);
+  assert_true(!await isOperationsChainEmpty(pc), "Non-empty queue");
+  await p;
+}, "setLocalDescription uses operations chain");
+
+promise_test(async t => {
+  const pc = new RTCPeerConnection();
+  t.add_cleanup(() => pc.close());
+  pc.createDataChannel("dummy");
+
+  const offer = await pc.createOffer();
+  assert_true(await isOperationsChainEmpty(pc), "Empty after settled");
+  const p = pc.setRemoteDescription(offer);
+  assert_true(!await isOperationsChainEmpty(pc), "Non-empty queue");
+  await p;
+}, "setRemoteDescription uses operations chain");
+
+promise_test(async t => {
+  const pc1 = new RTCPeerConnection();
+  t.add_cleanup(() => pc1.close());
+  const pc2 = new RTCPeerConnection();
+  t.add_cleanup(() => pc2.close());
+
+  pc1.addTransceiver("video");
+  const offer = await pc1.createOffer();
+  await pc1.setLocalDescription(offer);
+  const {candidate} = await new Promise(r => pc1.onicecandidate = r);
+  await pc2.setRemoteDescription(offer);
+  const p = pc2.addIceCandidate(candidate);
+  assert_true(!await isOperationsChainEmpty(pc2), "Non-empty queue");
+  await p;
+}, "addIceCandidate uses operations chain");
+
+</script>
diff --git a/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-setLocalDescription-parameterless.https.html b/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-setLocalDescription-parameterless.https.html
index 0cce78bfbca..5a7a76319a0 100644
--- a/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-setLocalDescription-parameterless.https.html
+++ b/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-setLocalDescription-parameterless.https.html
@@ -7,7 +7,7 @@
 <script>
 "use strict";
 
-const kSmallTimeoutMs = 10;
+const kSmallTimeoutMs = 100;
 
 promise_test(async t => {
   const offerer = new RTCPeerConnection();
@@ -34,6 +34,7 @@ promise_test(async t => {
   t.add_cleanup(() => offerer.close());
 
   const transceiver = offerer.addTransceiver('audio');
+  assert_equals(transceiver.mid, null);
   await offerer.setLocalDescription();
   assert_not_equals(transceiver.mid, null);
 }, "Parameterless SLD() in 'stable' assigns transceiver.mid");
@@ -110,20 +111,25 @@ promise_test(async t => {
 promise_test(async t => {
   const offerer = new RTCPeerConnection();
   offerer.close();
-
-  offerer.setLocalDescription().then(t.step_func(() => assert_not_reached()));
-  await new Promise(resolve => t.step_timeout(resolve, kSmallTimeoutMs));
-}, "Parameterless SLD() never resolves if already closed");
+  try {
+    await offerer.setLocalDescription();
+    assert_not_reached();
+  } catch (e) {
+    assert_equals(e.name, "InvalidStateError");
+  }
+}, "Parameterless SLD() rejects with InvalidStateError if already closed");
 
 promise_test(async t => {
   const offerer = new RTCPeerConnection();
   t.add_cleanup(() => offerer.close());
 
-  offerer.setLocalDescription().then(t.step_func(() => assert_not_reached()));
+  const p = Promise.race([
+    offerer.setLocalDescription(),
+    new Promise(r => t.step_timeout(() => r("timeout"), kSmallTimeoutMs))
+  ]);
   offerer.close();
-  await new Promise(resolve => t.step_timeout(resolve, kSmallTimeoutMs));
-}, "Parameterless SLD() never resolves if closed while pending");
-
+  assert_equals(await p, "timeout");
+}, "Parameterless SLD() never settles if closed while pending");
 
 promise_test(async t => {
   const offerer = new RTCPeerConnection();
@@ -139,4 +145,26 @@ promise_test(async t => {
   await offerer.setRemoteDescription(answerer.currentLocalDescription);
 }, "Parameterless SLD() in a full O/A exchange succeeds");
 
-</script>
\ No newline at end of file
+promise_test(async t => {
+  const answerer = new RTCPeerConnection();
+  try {
+    await answerer.setRemoteDescription();
+    assert_not_reached();
+  } catch (e) {
+    assert_equals(e.name, "TypeError");
+  }
+}, "Parameterless SRD() rejects with TypeError.");
+
+promise_test(async t => {
+  const offerer = new RTCPeerConnection();
+  const {sdp} = await offerer.createOffer();
+  new RTCSessionDescription({type: "offer", sdp});
+  try {
+    new RTCSessionDescription({sdp});
+    assert_not_reached();
+  } catch (e) {
+    assert_equals(e.name, "TypeError");
+  }
+}, "RTCSessionDescription constructed without type throws TypeError");
+
+</script>