diff --git a/tests/wpt/metadata/MANIFEST.json b/tests/wpt/metadata/MANIFEST.json
index 1eadfec9e19..3d5875b011c 100644
--- a/tests/wpt/metadata/MANIFEST.json
+++ b/tests/wpt/metadata/MANIFEST.json
@@ -317494,6 +317494,11 @@
      {}
     ]
    ],
+   "webrtc/legacy/README.txt": [
+    [
+     {}
+    ]
+   ],
    "webrtc/protocol/README.txt": [
     [
      {}
@@ -339351,6 +339356,12 @@
      {}
     ]
    ],
+   "css/css-position/inheritance.html": [
+    [
+     "/css/css-position/inheritance.html",
+     {}
+    ]
+   ],
    "css/css-position/position-sticky-bottom.html": [
     [
      "/css/css-position/position-sticky-bottom.html",
@@ -376505,6 +376516,12 @@
      {}
     ]
    ],
+   "mediacapture-record/MediaRecorder-error.html": [
+    [
+     "/mediacapture-record/MediaRecorder-error.html",
+     {}
+    ]
+   ],
    "mediacapture-record/MediaRecorder-stop.html": [
     [
      "/mediacapture-record/MediaRecorder-stop.html",
@@ -408711,6 +408728,12 @@
      {}
     ]
    ],
+   "webrtc-identity/RTCPeerConnection-constructor.html": [
+    [
+     "/webrtc-identity/RTCPeerConnection-constructor.html",
+     {}
+    ]
+   ],
    "webrtc-identity/RTCPeerConnection-getIdentityAssertion.sub.html": [
     [
      "/webrtc-identity/RTCPeerConnection-getIdentityAssertion.sub.html",
@@ -408893,12 +408916,6 @@
      {}
     ]
    ],
-   "webrtc/RTCPeerConnection-createOffer-offerToReceive.html": [
-    [
-     "/webrtc/RTCPeerConnection-createOffer-offerToReceive.html",
-     {}
-    ]
-   ],
    "webrtc/RTCPeerConnection-createOffer.html": [
     [
      "/webrtc/RTCPeerConnection-createOffer.html",
@@ -409229,6 +409246,24 @@
      {}
     ]
    ],
+   "webrtc/legacy/RTCPeerConnection-createOffer-offerToReceive.html": [
+    [
+     "/webrtc/legacy/RTCPeerConnection-createOffer-offerToReceive.html",
+     {}
+    ]
+   ],
+   "webrtc/legacy/RTCRtpTransceiver-with-OfferToReceive-options.https.html": [
+    [
+     "/webrtc/legacy/RTCRtpTransceiver-with-OfferToReceive-options.https.html",
+     {}
+    ]
+   ],
+   "webrtc/legacy/onaddstream.https.html": [
+    [
+     "/webrtc/legacy/onaddstream.https.html",
+     {}
+    ]
+   ],
    "webrtc/no-media-call.html": [
     [
      "/webrtc/no-media-call.html",
@@ -409241,6 +409276,12 @@
      {}
     ]
    ],
+   "webrtc/protocol/jsep-initial-offer.https.html": [
+    [
+     "/webrtc/protocol/jsep-initial-offer.https.html",
+     {}
+    ]
+   ],
    "webrtc/protocol/video-codecs.https.html": [
     [
      "/webrtc/protocol/video-codecs.https.html",
@@ -556512,6 +556553,10 @@
    "9ccb822f107f429651c7949995412c9f2a80feea",
    "reftest"
   ],
+  "css/css-position/inheritance.html": [
+   "d75b28c1e0aa2698fe0c73965f4e7d1f06b16547",
+   "testharness"
+  ],
   "css/css-position/position-relative-table-left-ref.html": [
    "7c1193b80007d8e7f89b35400a6d2ea2266cb3ac",
    "support"
@@ -627392,6 +627437,10 @@
    "1710d238b6e31d285766f25f4625d206d1d8a1fc",
    "testharness"
   ],
+  "mediacapture-record/MediaRecorder-error.html": [
+   "2459449acf931cd38301fca11e7b15326afac040",
+   "testharness"
+  ],
   "mediacapture-record/MediaRecorder-stop.html": [
    "8e05fc5491d8da7aaddefea20fae36d705c75bce",
    "testharness"
@@ -669212,6 +669261,10 @@
    "900769b9d4334bb38d6413beea6a28235d8c927c",
    "support"
   ],
+  "webrtc-identity/RTCPeerConnection-constructor.html": [
+   "8498e6b35c9ff820c86773dd874930c5b012229e",
+   "testharness"
+  ],
   "webrtc-identity/RTCPeerConnection-getIdentityAssertion.sub.html": [
    "2bd860d901ded78c9635da65413ac63e7dbf4460",
    "testharness"
@@ -669333,7 +669386,7 @@
    "testharness"
   ],
   "webrtc/RTCPeerConnection-addTrack.https.html": [
-   "2ec9a1f7d60d84fce6e5a8b240b0fadc3b1d910f",
+   "1550fc4f7943b79cc331d5c93ca6d5643793dead",
    "testharness"
   ],
   "webrtc/RTCPeerConnection-addTransceiver.https.html": [
@@ -669349,23 +669402,19 @@
    "testharness"
   ],
   "webrtc/RTCPeerConnection-constructor.html": [
-   "e00d98709087eea37599e5c7d520b04cbb6e1e8f",
+   "abea2eb6761b779ba527b75660d0c2258c805ba1",
    "testharness"
   ],
   "webrtc/RTCPeerConnection-createAnswer.html": [
-   "abff1eb7329cceda286216b90531f997040ed474",
+   "030ced8c98f4c926c5af870bf16097f4f56a7d1e",
    "testharness"
   ],
   "webrtc/RTCPeerConnection-createDataChannel.html": [
    "450a25002ed2212e7f1dd5cb97ff985e3f957aa1",
    "testharness"
   ],
-  "webrtc/RTCPeerConnection-createOffer-offerToReceive.html": [
-   "dd1827a1c8d60abe67cad72a9ef3280003c792c0",
-   "testharness"
-  ],
   "webrtc/RTCPeerConnection-createOffer.html": [
-   "2fa3a05f60a1a53668e9978009958a19c57e4fc1",
+   "c56d45280ef6317bc0ef77b8ad71e9273c809863",
    "testharness"
   ],
   "webrtc/RTCPeerConnection-generateCertificate.html": [
@@ -669385,7 +669434,7 @@
    "testharness"
   ],
   "webrtc/RTCPeerConnection-helper.js": [
-   "330ce1992d97a5d3fc825f882fcdaa3f1f4a95bf",
+   "8529fb4ef3cdf509a519608fbb4a5919c44f3e37",
    "support"
   ],
   "webrtc/RTCPeerConnection-iceConnectionState.html": [
@@ -669421,15 +669470,15 @@
    "testharness"
   ],
   "webrtc/RTCPeerConnection-setLocalDescription-answer.html": [
-   "4a50456f21613a39946c54774377aef176c04486",
+   "b783d854738a926cfdf0ecc7ecd7897b5b86b200",
    "testharness"
   ],
   "webrtc/RTCPeerConnection-setLocalDescription-offer.html": [
-   "9502f283f55081300f80a0f06650f28eb46ce506",
+   "49eb522881a9abb914566b42a5e7aae7063fdb8b",
    "testharness"
   ],
   "webrtc/RTCPeerConnection-setLocalDescription-pranswer.html": [
-   "a145f95afa3521d6ec8446e12da41d19d338b9a7",
+   "1fbb30923f3d1e9abef6940a931a6d426ed01915",
    "testharness"
   ],
   "webrtc/RTCPeerConnection-setLocalDescription-rollback.html": [
@@ -669437,11 +669486,11 @@
    "testharness"
   ],
   "webrtc/RTCPeerConnection-setLocalDescription.html": [
-   "0ab2db1d56d4163aa088776c51d652cedece15a7",
+   "1030f494f2469c2fceaa618e2992397b5a4bbb8f",
    "testharness"
   ],
   "webrtc/RTCPeerConnection-setRemoteDescription-answer.html": [
-   "ff554478af833a2a9b56a7a863d37a0255bca7b6",
+   "cc5bd1e0807b71e0e96c368fe18ab6bd0c6d142d",
    "testharness"
   ],
   "webrtc/RTCPeerConnection-setRemoteDescription-offer.html": [
@@ -669449,7 +669498,7 @@
    "testharness"
   ],
   "webrtc/RTCPeerConnection-setRemoteDescription-pranswer.html": [
-   "9197a359671bd1d8f28098b2a8db1b93ee181cee",
+   "c27ee20855bea03e4aa8a2ca80b90653f5e9d5b5",
    "testharness"
   ],
   "webrtc/RTCPeerConnection-setRemoteDescription-replaceTrack.https.html": [
@@ -669457,7 +669506,7 @@
    "testharness"
   ],
   "webrtc/RTCPeerConnection-setRemoteDescription-rollback.html": [
-   "01969dce310c78561d97f22a0cc6da9390bf0c27",
+   "ec90e561cbcf76559356dcd46c77547fb8262dcb",
    "testharness"
   ],
   "webrtc/RTCPeerConnection-setRemoteDescription-tracks.https.html": [
@@ -669465,7 +669514,7 @@
    "testharness"
   ],
   "webrtc/RTCPeerConnection-setRemoteDescription.html": [
-   "ad9cdff5fb0a4cf90e977fd0cdde7d3d685e9f4d",
+   "182abea403ed7bee6568aac402cbb6a8caac6159",
    "testharness"
   ],
   "webrtc/RTCPeerConnection-track-stats.https.html": [
@@ -669533,11 +669582,11 @@
    "testharness"
   ],
   "webrtc/RTCRtpReceiver-getParameters.html": [
-   "97e5d10d1e53b18d3c9deca969d2046881418569",
+   "453844d5f0e63cf6690ca8eb5fe3335073d34921",
    "testharness"
   ],
   "webrtc/RTCRtpReceiver-getStats.https.html": [
-   "4a2e6a0bd8b0ac9528ed4eeb0b47fea83b26c54f",
+   "05ca9f3c90b652a4c46a0395bf2ad1a6eb44e15f",
    "testharness"
   ],
   "webrtc/RTCRtpReceiver-getSynchronizationSources.https.html": [
@@ -669549,7 +669598,7 @@
    "testharness"
   ],
   "webrtc/RTCRtpSender-getStats.https.html": [
-   "18ab82555447194dbacfb07aa5715953c0f17dde",
+   "1af8285f4c325f38b322d26aa582f3bed7f70585",
    "testharness"
   ],
   "webrtc/RTCRtpSender-replaceTrack.https.html": [
@@ -669569,15 +669618,15 @@
    "testharness"
   ],
   "webrtc/RTCRtpTransceiver.https.html": [
-   "860f5de2d2aca4b3cbcc6e201c8dc774f154346f",
+   "2de9fb9f6ee4dbc555bf30ba46f21df30385dd5c",
    "testharness"
   ],
   "webrtc/RTCSctpTransport-constructor.html": [
-   "c415c3fe180b6718fa11c20b1bc9a1ecd88a4547",
+   "7d3df051d876e490c926639499c13ba0dcf8d30a",
    "testharness"
   ],
   "webrtc/RTCSctpTransport-maxMessageSize.html": [
-   "28d17eeaccf3f26aaca93c9e1f1eab9edc643aaa",
+   "9163a66af151e3e2f13ab7c4a40e56e3f162c97f",
    "testharness"
   ],
   "webrtc/RTCStats-helper.js": [
@@ -669609,7 +669658,7 @@
    "support"
   ],
   "webrtc/getstats.html": [
-   "937f54b74ec8266f890d60a4c67e75c3d6714826",
+   "053d9092ceb6f1ca6900d164ee10965c001f2a0c",
    "testharness"
   ],
   "webrtc/historical.html": [
@@ -669620,8 +669669,24 @@
    "3c57a022cabfbedcf4a015024ac88ecd3080faf6",
    "testharness"
   ],
+  "webrtc/legacy/README.txt": [
+   "8adbf6aa173949718a90bd54cc95361e1a8801ba",
+   "support"
+  ],
+  "webrtc/legacy/RTCPeerConnection-createOffer-offerToReceive.html": [
+   "f710498e75f1be587c66d1d0dfe215cb136cc747",
+   "testharness"
+  ],
+  "webrtc/legacy/RTCRtpTransceiver-with-OfferToReceive-options.https.html": [
+   "8c2975214c4dce28a41336de128e0c54c0800828",
+   "testharness"
+  ],
+  "webrtc/legacy/onaddstream.https.html": [
+   "5aa16b36a24e1bce3c286cc5aec249a891bf76f0",
+   "testharness"
+  ],
   "webrtc/no-media-call.html": [
-   "8f4f5962d4af9de8fd25b9a64aedb49c7b0a0824",
+   "0f2e2a33e62b47292085c14ad36a253d800c5982",
    "testharness"
   ],
   "webrtc/promises-call.html": [
@@ -669632,8 +669697,12 @@
    "062db8540f43278b7a49a94c3fa25647f038ef8f",
    "support"
   ],
+  "webrtc/protocol/jsep-initial-offer.https.html": [
+   "88bdfcfc2867335ca53c30f5637b38b3d12c64ca",
+   "testharness"
+  ],
   "webrtc/protocol/video-codecs.https.html": [
-   "547856f2a271b5c349b529ec7f1fe1acb5a48ef0",
+   "e728effbeb94de865df9f8860cd45c8de1f601c1",
    "testharness"
   ],
   "webrtc/resources/RTCCertificate-postMessage-iframe.html": [
diff --git a/tests/wpt/metadata/css/compositing/mix-blend-mode/mix-blend-mode-animation.html.ini b/tests/wpt/metadata/css/compositing/mix-blend-mode/mix-blend-mode-animation.html.ini
new file mode 100644
index 00000000000..5496474410b
--- /dev/null
+++ b/tests/wpt/metadata/css/compositing/mix-blend-mode/mix-blend-mode-animation.html.ini
@@ -0,0 +1,2 @@
+[mix-blend-mode-animation.html]
+  expected: FAIL
diff --git a/tests/wpt/metadata/css/css-transitions/transitions-animatable-properties-01.html.ini b/tests/wpt/metadata/css/css-transitions/transitions-animatable-properties-01.html.ini
index 8850ec200da..f07f9ef2353 100644
--- a/tests/wpt/metadata/css/css-transitions/transitions-animatable-properties-01.html.ini
+++ b/tests/wpt/metadata/css/css-transitions/transitions-animatable-properties-01.html.ini
@@ -74,3 +74,9 @@
   [opacity end]
     expected: FAIL
 
+  [border-top-width end]
+    expected: FAIL
+
+  [border-right-width end]
+    expected: FAIL
+
diff --git a/tests/wpt/metadata/html/browsers/browsing-the-web/navigating-across-documents/006.html.ini b/tests/wpt/metadata/html/browsers/browsing-the-web/navigating-across-documents/006.html.ini
deleted file mode 100644
index c8544361068..00000000000
--- a/tests/wpt/metadata/html/browsers/browsing-the-web/navigating-across-documents/006.html.ini
+++ /dev/null
@@ -1,4 +0,0 @@
-[006.html]
-  [Link with onclick form submit and href navigation ]
-    expected: FAIL
-
diff --git a/tests/wpt/metadata/html/browsers/history/the-history-interface/traverse_the_history_1.html.ini b/tests/wpt/metadata/html/browsers/history/the-history-interface/traverse_the_history_1.html.ini
deleted file mode 100644
index 87b07c3e670..00000000000
--- a/tests/wpt/metadata/html/browsers/history/the-history-interface/traverse_the_history_1.html.ini
+++ /dev/null
@@ -1,4 +0,0 @@
-[traverse_the_history_1.html]
-  [Multiple history traversals from the same task]
-    expected: FAIL
-
diff --git a/tests/wpt/metadata/html/browsers/history/the-history-interface/traverse_the_history_5.html.ini b/tests/wpt/metadata/html/browsers/history/the-history-interface/traverse_the_history_5.html.ini
deleted file mode 100644
index dc2e45516de..00000000000
--- a/tests/wpt/metadata/html/browsers/history/the-history-interface/traverse_the_history_5.html.ini
+++ /dev/null
@@ -1,4 +0,0 @@
-[traverse_the_history_5.html]
-  [Multiple history traversals, last would be aborted]
-    expected: FAIL
-
diff --git a/tests/wpt/metadata/html/browsers/history/the-location-interface/location-protocol-setter-non-broken.html.ini b/tests/wpt/metadata/html/browsers/history/the-location-interface/location-protocol-setter-non-broken.html.ini
index 18c00592997..63ed71e8409 100644
--- a/tests/wpt/metadata/html/browsers/history/the-location-interface/location-protocol-setter-non-broken.html.ini
+++ b/tests/wpt/metadata/html/browsers/history/the-location-interface/location-protocol-setter-non-broken.html.ini
@@ -18,18 +18,6 @@
   [Set data URL frame location.protocol to http+x]
     expected: FAIL
 
-  [Set HTTP URL frame location.protocol to data]
-    expected: FAIL
-
-  [Set HTTP URL frame location.protocol to gopher]
-    expected: FAIL
-
-  [Set HTTP URL frame location.protocol to http+x]
-    expected: FAIL
-
-  [Set HTTP URL frame location.protocol to ftp]
-    expected: FAIL
-
   [Set HTTP URL frame location.protocol to x]
     expected: FAIL
 
diff --git a/tests/wpt/metadata/html/semantics/embedded-content/the-img-element/non-active-document.html.ini b/tests/wpt/metadata/html/semantics/embedded-content/the-img-element/non-active-document.html.ini
deleted file mode 100644
index 8cc42056d34..00000000000
--- a/tests/wpt/metadata/html/semantics/embedded-content/the-img-element/non-active-document.html.ini
+++ /dev/null
@@ -1,10 +0,0 @@
-[non-active-document.html]
-  [DOMParser]
-    expected: FAIL
-
-  [createHTMLDocument]
-    expected: FAIL
-
-  [<template>]
-    expected: FAIL
-
diff --git a/tests/wpt/metadata/html/semantics/interactive-elements/the-details-element/toggleEvent.html.ini b/tests/wpt/metadata/html/semantics/interactive-elements/the-details-element/toggleEvent.html.ini
new file mode 100644
index 00000000000..9e522297c94
--- /dev/null
+++ b/tests/wpt/metadata/html/semantics/interactive-elements/the-details-element/toggleEvent.html.ini
@@ -0,0 +1,7 @@
+[toggleEvent.html]
+  [Calling open twice on 'details' fires only one toggle event]
+    expected: FAIL
+
+  [Setting open=true to opened 'details' element should not fire a toggle event at the 'details' element]
+    expected: FAIL
+
diff --git a/tests/wpt/metadata/performance-timeline/webtiming-resolution.any.js.ini b/tests/wpt/metadata/performance-timeline/webtiming-resolution.any.js.ini
index 7725b118e9d..99a24216c88 100644
--- a/tests/wpt/metadata/performance-timeline/webtiming-resolution.any.js.ini
+++ b/tests/wpt/metadata/performance-timeline/webtiming-resolution.any.js.ini
@@ -12,6 +12,3 @@
   [Verifies the resolution of entry.startTime is at least 5 microseconds.]
     expected: TIMEOUT
 
-  [Verifies the resolution of performance.now() is at least 5 microseconds.]
-    expected: FAIL
-
diff --git a/tests/wpt/metadata/quirks/unitless-length/no-quirks.html.ini b/tests/wpt/metadata/quirks/unitless-length/no-quirks.html.ini
deleted file mode 100644
index 818a429ed39..00000000000
--- a/tests/wpt/metadata/quirks/unitless-length/no-quirks.html.ini
+++ /dev/null
@@ -1,283 +0,0 @@
-[no-quirks.html]
-  [top: -\\31 .5]
-    expected: FAIL
-
-  [bottom: -1A]
-    expected: FAIL
-
-  [bottom: -1a]
-    expected: FAIL
-
-  [top: @1]
-    expected: FAIL
-
-  [top: "1a"]
-    expected: FAIL
-
-  [top: @a]
-    expected: FAIL
-
-  [bottom: "1"]
-    expected: FAIL
-
-  [bottom: -/**/1]
-    expected: FAIL
-
-  [top: +/**/1]
-    expected: FAIL
-
-  [bottom: @1a]
-    expected: FAIL
-
-  [top: 1\\31 ]
-    expected: FAIL
-
-  [top: url('1')]
-    expected: FAIL
-
-  [bottom: -\\31 ]
-    expected: FAIL
-
-  [top: calc(1)]
-    expected: FAIL
-
-  [top: \\31 ]
-    expected: FAIL
-
-  [bottom: +1\\31 ]
-    expected: FAIL
-
-  [bottom: 1\\31 .5]
-    expected: FAIL
-
-  [bottom: #0001]
-    expected: FAIL
-
-  [top: calc(2 * 2px)]
-    expected: FAIL
-
-  [bottom: 1a]
-    expected: FAIL
-
-  [bottom: A]
-    expected: FAIL
-
-  [bottom: #01]
-    expected: FAIL
-
-  [top: +\\31 .5]
-    expected: FAIL
-
-  [bottom: #1]
-    expected: FAIL
-
-  [top: -/**/1]
-    expected: FAIL
-
-  [bottom: +\\31 .5]
-    expected: FAIL
-
-  [bottom: \\31 ]
-    expected: FAIL
-
-  [bottom: calc(1)]
-    expected: FAIL
-
-  [top: #001]
-    expected: FAIL
-
-  [top: +\\31 ]
-    expected: FAIL
-
-  [bottom: +\\31 ]
-    expected: FAIL
-
-  [top: +1.5]
-    expected: FAIL
-
-  [top: +1\\31 ]
-    expected: FAIL
-
-  [bottom: @a]
-    expected: FAIL
-
-  [bottom: @1]
-    expected: FAIL
-
-  [top: #1]
-    expected: FAIL
-
-  [top: 1a]
-    expected: FAIL
-
-  [bottom: +1a]
-    expected: FAIL
-
-  [bottom: +1A]
-    expected: FAIL
-
-  [bottom: "a"]
-    expected: FAIL
-
-  [top: #00001]
-    expected: FAIL
-
-  [bottom: -1\\31 .5]
-    expected: FAIL
-
-  [top: "1"]
-    expected: FAIL
-
-  [bottom: 1.5]
-    expected: FAIL
-
-  [bottom: -\\31 .5]
-    expected: FAIL
-
-  [bottom: url('1')]
-    expected: FAIL
-
-  [bottom: -1.5]
-    expected: FAIL
-
-  [top: \\31 .5]
-    expected: FAIL
-
-  [bottom: "1a"]
-    expected: FAIL
-
-  [bottom: calc(2 * 2px)]
-    expected: FAIL
-
-  [bottom: +1\\31 .5]
-    expected: FAIL
-
-  [bottom: 1\\31 ]
-    expected: FAIL
-
-  [bottom: +/**/1]
-    expected: FAIL
-
-  [bottom: #00001]
-    expected: FAIL
-
-  [top: url(1)]
-    expected: FAIL
-
-  [bottom: #001]
-    expected: FAIL
-
-  [top: +1\\31 .5]
-    expected: FAIL
-
-  [top: -1a]
-    expected: FAIL
-
-  [top: -1A]
-    expected: FAIL
-
-  [bottom: url(1)]
-    expected: FAIL
-
-  [top: a]
-    expected: FAIL
-
-  [top: A]
-    expected: FAIL
-
-  [top: #000001]
-    expected: FAIL
-
-  [top: 1]
-    expected: FAIL
-
-  [top: 1\\31 .5]
-    expected: FAIL
-
-  [bottom: a]
-    expected: FAIL
-
-  [bottom: 1]
-    expected: FAIL
-
-  [bottom: +1]
-    expected: FAIL
-
-  [bottom: #000001]
-    expected: FAIL
-
-  [bottom: +a]
-    expected: FAIL
-
-  [bottom: +A]
-    expected: FAIL
-
-  [top: 1.5]
-    expected: FAIL
-
-  [top: +A]
-    expected: FAIL
-
-  [top: +a]
-    expected: FAIL
-
-  [top: +1]
-    expected: FAIL
-
-  [top: -1.5]
-    expected: FAIL
-
-  [top: -1\\31 .5]
-    expected: FAIL
-
-  [top: +1a]
-    expected: FAIL
-
-  [top: +1A]
-    expected: FAIL
-
-  [top: @1a]
-    expected: FAIL
-
-  [bottom: \\31 .5]
-    expected: FAIL
-
-  [top: "a"]
-    expected: FAIL
-
-  [top: #01]
-    expected: FAIL
-
-  [bottom: +1.5]
-    expected: FAIL
-
-  [bottom: -A]
-    expected: FAIL
-
-  [bottom: -a]
-    expected: FAIL
-
-  [bottom: -1\\31 ]
-    expected: FAIL
-
-  [top: #0001]
-    expected: FAIL
-
-  [bottom: -1]
-    expected: FAIL
-
-  [top: -\\31 ]
-    expected: FAIL
-
-  [top: -A]
-    expected: FAIL
-
-  [top: -a]
-    expected: FAIL
-
-  [top: -1]
-    expected: FAIL
-
-  [top: -1\\31 ]
-    expected: FAIL
-
diff --git a/tests/wpt/metadata/url/urlencoded-parser.any.js.ini b/tests/wpt/metadata/url/urlencoded-parser.any.js.ini
index e3f54ad9ede..8fa49422e95 100644
--- a/tests/wpt/metadata/url/urlencoded-parser.any.js.ini
+++ b/tests/wpt/metadata/url/urlencoded-parser.any.js.ini
@@ -8,35 +8,20 @@
   [response.formData() with input: a&b&c]
     expected: FAIL
 
-  [response.formData() with input: _charset_=windows-1252&test=%C2x]
-    expected: FAIL
-
   [response.formData() with input: &&&a=b&&&&c=d&]
     expected: FAIL
 
-  [request.formData() with input: &&&a=b&&&&c=d&]
-    expected: FAIL
-
-  [response.formData() with input: a=b&c=d]
-    expected: FAIL
-
 
 [urlencoded-parser.any.worker.html]
   [request.formData() with input: a&b&c]
     expected: FAIL
 
-  [request.formData() with input: a=b&c=d&]
-    expected: FAIL
-
-  [request.formData() with input: &&&a=b&&&&c=d&]
-    expected: FAIL
-
   [response.formData() with input: a&b&c]
     expected: FAIL
 
   [response.formData() with input: a=b&c=d&]
     expected: FAIL
 
-  [response.formData() with input: _charset_=windows-1252&test=%C2x]
+  [response.formData() with input: a=b&c=d]
     expected: FAIL
 
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/mozilla/meta/mozilla/paint_timing.html.ini b/tests/wpt/mozilla/meta/mozilla/paint_timing.html.ini
deleted file mode 100644
index 14a9e778f39..00000000000
--- a/tests/wpt/mozilla/meta/mozilla/paint_timing.html.ini
+++ /dev/null
@@ -1,4 +0,0 @@
-[paint_timing.html]
-  [Performance entries observer]
-    expected: FAIL
-
diff --git a/tests/wpt/web-platform-tests/css/css-position/inheritance.html b/tests/wpt/web-platform-tests/css/css-position/inheritance.html
new file mode 100644
index 00000000000..d75b28c1e0a
--- /dev/null
+++ b/tests/wpt/web-platform-tests/css/css-position/inheritance.html
@@ -0,0 +1,35 @@
+<!DOCTYPE html>
+<html>
+<head>
+<meta charset="utf-8">
+<title>Inheritance of CSS Positioned Layout properties</title>
+<link rel="help" href="https://drafts.csswg.org/css-position/#property-index">
+<meta name="assert" content="Properties inherit or not according to the spec.">
+<meta name="assert" content="Properties have initial values according to the spec.">
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<script src="/css/support/inheritance-testcommon.js"></script>
+</head>
+<body>
+<div id="container">
+<div id="target"></div>
+</div>
+<style>
+#container, #target {
+  position: sticky;
+}
+</style>
+<script>
+assert_not_inherited('position', 'static', 'absolute');
+assert_not_inherited('top', 'auto', '10px');
+assert_not_inherited('right', 'auto', '10px');
+assert_not_inherited('bottom', 'auto', '10px');
+assert_not_inherited('left', 'auto', '10px');
+assert_not_inherited('inset-before', 'auto', '10px');
+assert_not_inherited('inset-after', 'auto', '10px');
+assert_not_inherited('inset-start', 'auto', '10px');
+assert_not_inherited('inset-end', 'auto', '10px');
+assert_not_inherited('z-index', 'auto', '123');
+</script>
+</body>
+</html>
diff --git a/tests/wpt/web-platform-tests/mediacapture-record/MediaRecorder-error.html b/tests/wpt/web-platform-tests/mediacapture-record/MediaRecorder-error.html
new file mode 100644
index 00000000000..2459449acf9
--- /dev/null
+++ b/tests/wpt/web-platform-tests/mediacapture-record/MediaRecorder-error.html
@@ -0,0 +1,75 @@
+<!doctype html>
+<html>
+<head>
+    <title>MediaRecorder Error</title>
+    <link rel="help" href="https://w3c.github.io/mediacapture-record/MediaRecorder.html#mediarecorder">
+    <script src="/resources/testharness.js"></script>
+    <script src="/resources/testharnessreport.js"></script>
+</head>
+<body>
+<canvas id="canvas" width="320" height="320">
+</canvas>
+<script>
+    function createAudioStream() {
+        let ac = new AudioContext();
+        let osc = ac.createOscillator();
+        let dest = ac.createMediaStreamDestination();
+        osc.connect(dest);
+        return dest.stream;
+    }
+
+    function createVideoStream() {
+        let canvas = document.getElementById("canvas");
+        canvas.getContext('2d').lineTo(10, 10);
+        return canvas.captureStream();
+    }
+
+    async_test(t => {
+        let video = createVideoStream();
+        let audio = createAudioStream();
+        let recorder = new MediaRecorder(video);
+        recorder.onerror = t.step_func(mediaRecorderErrorEvent => {
+            assert_true(mediaRecorderErrorEvent instanceof MediaRecorderErrorEvent, 'the type of event should be MediaRecorderErrorEvent');
+            assert_equals(mediaRecorderErrorEvent.error.name, 'UnknownError', 'the type of error should be UnknownError when track has been added or removed');
+            assert_true(mediaRecorderErrorEvent.isTrusted, 'isTrusted should be true when the event is created by C++');
+            assert_equals(recorder.state, "inactive", "MediaRecorder has been stopped after adding a track to stream");
+            t.done();
+        });
+        recorder.start();
+        assert_equals(recorder.state, "recording", "MediaRecorder has been started successfully");
+        video.addTrack(audio.getAudioTracks()[0]);
+        t.step_timeout(() => {
+            assert_unreached("error event is not fired after 2 seconds");
+        }, 2000);
+    }, "MediaRecorder will stop recording when any of track is added and error event will be fired");
+
+    async_test(t => {
+        let video = createVideoStream();
+        let recorder = new MediaRecorder(video);
+        recorder.onerror = t.step_func(mediaRecorderErrorEvent => {
+            assert_true(mediaRecorderErrorEvent instanceof MediaRecorderErrorEvent, 'the type of event should be MediaRecorderErrorEvent');
+            assert_equals(mediaRecorderErrorEvent.error.name, 'UnknownError', 'the type of error should be UnknownError when track has been added or removed');
+            assert_true(mediaRecorderErrorEvent.isTrusted, 'isTrusted should be true when the event is created by C++');
+            assert_equals(recorder.state, "inactive", "MediaRecorder has been stopped after removing a track from stream");
+            t.done();
+        });
+        recorder.start();
+        assert_equals(recorder.state, "recording", "MediaRecorder has been started successfully");
+        video.removeTrack(video.getVideoTracks()[0]);
+        t.step_timeout(() => {
+            assert_unreached("error event is not fired after 2 seconds");
+        }, 2000);
+    }, "MediaRecorder will stop recording when any of track is removed and error event will be fired");
+
+    test(t => {
+        let video = createVideoStream();
+        let recorder = new MediaRecorder(video);
+        recorder.start();
+        assert_equals(recorder.state, "recording", "MediaRecorder has been started successfully");
+        assert_throws("InvalidStateError", function() {
+            recorder.start();
+        });
+    }, "MediaRecorder cannot start recording when MediaRecorder' state is not inactive and an InvalidStateError should be thrown");
+</script>
+</body>
+</html>
diff --git a/tests/wpt/web-platform-tests/webrtc-identity/RTCPeerConnection-constructor.html b/tests/wpt/web-platform-tests/webrtc-identity/RTCPeerConnection-constructor.html
new file mode 100644
index 00000000000..8498e6b35c9
--- /dev/null
+++ b/tests/wpt/web-platform-tests/webrtc-identity/RTCPeerConnection-constructor.html
@@ -0,0 +1,11 @@
+<!doctype html>
+<meta charset=utf-8>
+<title>RTCPeerConnection constructor</title>
+<script src=/resources/testharness.js></script>
+<script src=/resources/testharnessreport.js></script>
+<script>
+test(() => {
+    const toStringThrows = { toString: function() { throw new Error; } };
+    assert_throws(new Error, () => new RTCPeerConnection({ peerIdentity: toStringThrows }));
+}, "RTCPeerConnection constructor throws if the given peerIdentity getter throws");
+</script>
diff --git a/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-addTrack.https.html b/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-addTrack.https.html
index 2ec9a1f7d60..1550fc4f794 100644
--- a/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-addTrack.https.html
+++ b/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-addTrack.https.html
@@ -276,19 +276,6 @@
             createAnswer to mark the corresponding media description as sendrecv
             or sendonly and add the MSID of the track added, as defined in [JSEP]
             (section 5.2.2. and section 5.3.2.).
-        9.  A track could have contents that are inaccessible to the application.
-            This can be due to being marked with a peerIdentity option or anything
-            that would make a track CORS cross-origin. These tracks can be supplied
-            to the addTrack method, and have an RTCRtpSender created for them, but
-            content must not be transmitted, unless they are also marked with
-            peerIdentity and they meet the requirements for sending (see isolated
-            streams and RTCPeerConnection).
-
-            All other tracks that are not accessible to the application must not be
-            sent to the peer, with silence (audio), black frames (video) or
-            equivalently absent content being sent in place of track content.
-
-            Note that this property can change over time.
 
     Non-Testable
       5.1.  addTrack
diff --git a/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-constructor.html b/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-constructor.html
index e00d9870908..abea2eb6761 100644
--- a/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-constructor.html
+++ b/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-constructor.html
@@ -23,9 +23,6 @@ const testArgs = {
   'undefined': false,
   '{}': false,
 
-  // peerIdentity
-  '{ peerIdentity: toStringThrows }': new Error,
-
   // certificates
   '{ certificates: null }': new TypeError,
   '{ certificates: undefined }': false,
diff --git a/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-createAnswer.html b/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-createAnswer.html
index abff1eb7329..030ced8c98f 100644
--- a/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-createAnswer.html
+++ b/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-createAnswer.html
@@ -11,8 +11,7 @@
   // https://w3c.github.io/webrtc-pc/archives/20170515/webrtc.html
 
   // The following helper functions are called from RTCPeerConnection-helper.js:
-  //   generateOffer()
-  //   generateAnswer()
+  //   generateDataChannelOffer()
 
   /*
    * 4.3.2. createAnswer()
@@ -39,7 +38,7 @@
 
     t.add_cleanup(() => pc.close());
 
-    return pc.createOffer({ offerToReceiveVideo: true })
+    return generateVideoReceiveOnlyOffer(pc)
     .then(offer => pc.setRemoteDescription(offer))
     .then(() => pc.createAnswer())
     .then(answer => {
@@ -56,7 +55,7 @@
 
     t.add_cleanup(() => pc.close());
 
-    return generateOffer({ pc, data: true })
+    return generateDataChannelOffer(pc)
     .then(offer => pc.setRemoteDescription(offer))
     .then(() => {
       pc.close();
diff --git a/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-createOffer.html b/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-createOffer.html
index 2fa3a05f60a..c56d45280ef 100644
--- a/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-createOffer.html
+++ b/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-createOffer.html
@@ -11,8 +11,6 @@
   // https://w3c.github.io/webrtc-pc/archives/20170515/webrtc.html
 
   // The following helper functions are called from RTCPeerConnection-helper.js:
-  //   generateOffer()
-  //   generateAnswer()
   //   countAudioLine()
   //   countVideoLine()
   //   assert_session_desc_similar()
@@ -49,7 +47,7 @@
     const states = [];
     pc.addEventListener('signalingstatechange', () => states.push(pc.signalingState));
 
-    return pc.createOffer({ offerToReceiveAudio: true })
+    return generateVideoReceiveOnlyOffer(pc)
     .then(offer =>
       pc.setLocalDescription(offer)
       .then(() => {
@@ -113,93 +111,4 @@
    *    5.  If this inspection failed for any reason, reject p with a newly created
    *        OperationError and abort these steps.
    */
-
-  /*
-   *  4.3.3.2 Configuration data extensions
-   *  partial dictionary RTCOfferOptions
-   */
-
-  /*
-   *  offerToReceiveAudio of type boolean
-   *    When this is given a non-false value, no outgoing track of type
-   *    "audio" is attached to the PeerConnection, and the existing
-   *    localDescription (if any) doesn't contain any sendrecv or recv
-   *    audio media sections, createOffer() will behave as if
-   *    addTransceiver("audio") had been called once prior to the createOffer() call.
-   */
-  promise_test(t => {
-    const pc = new RTCPeerConnection();
-
-    t.add_cleanup(() => pc.close());
-
-    return pc.createOffer({ offerToReceiveAudio: true })
-    .then(offer1 => {
-      assert_equals(countAudioLine(offer1.sdp), 1,
-        'Expect created offer to have audio line');
-
-      // The first createOffer implicitly calls addTransceiver('audio'),
-      // so all following offers will also have audio media section
-      // in their SDP.
-      return pc.createOffer({ offerToReceiveAudio: false })
-      .then(offer2 => {
-        assert_equals(countAudioLine(offer2.sdp), 1,
-          'Expect audio line to remain in created offer');
-      })
-    });
-  }, 'createOffer() with offerToReceiveAudio should add audio line to all subsequent created offers');
-
-  /*
-   *  offerToReceiveVideo of type boolean
-   *    When this is given a non-false value, and no outgoing track
-   *    of type "video" is attached to the PeerConnection, and the
-   *    existing localDescription (if any) doesn't contain any sendecv
-   *    or recv video media sections, createOffer() will behave as if
-   *    addTransceiver("video") had been called prior to the createOffer() call.
-   */
-  promise_test(t => {
-    const pc = new RTCPeerConnection();
-
-    t.add_cleanup(() => pc.close());
-
-    return pc.createOffer({ offerToReceiveVideo: true })
-    .then(offer1 => {
-      assert_equals(countVideoLine(offer1.sdp), 1,
-      'Expect created offer to have video line');
-
-      return pc.createOffer({ offerToReceiveVideo: false })
-      .then(offer2 => {
-        assert_equals(countVideoLine(offer2.sdp), 1,
-          'Expect video line to remain in created offer');
-      })
-    });
-  }, 'createOffer() with offerToReceiveVideo should add video line to all subsequent created offers');
-
-  promise_test(t => {
-    const pc = new RTCPeerConnection();
-
-    t.add_cleanup(() => pc.close());
-
-    return pc.createOffer({
-      offerToReceiveAudio: true,
-      offerToReceiveVideo: false
-    }).then(offer1 => {
-      assert_equals(countAudioLine(offer1.sdp), 1,
-        'Expect audio line to be found in created offer');
-
-      assert_equals(countVideoLine(offer1.sdp), 0,
-        'Expect video line to not found in create offer');
-
-      return pc.createOffer({
-        offerToReceiveAudio: false,
-        offerToReceiveVideo: true
-      }).then(offer2 => {
-        assert_equals(countAudioLine(offer2.sdp), 1,
-          'Expect audio line to remain in created offer');
-
-        assert_equals(countVideoLine(offer2.sdp), 1,
-          'Expect video line to be found in create offer');
-      })
-    });
-  }, 'createOffer() with offerToReceiveAudio:true then offerToReceiveVideo:true should have result offer with both audio and video line');
-
 </script>
diff --git a/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-helper.js b/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-helper.js
index 330ce1992d9..8529fb4ef3c 100644
--- a/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-helper.js
+++ b/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-helper.js
@@ -103,73 +103,41 @@ function assert_session_desc_not_similar(sessionDesc1, sessionDesc2) {
     'Expect both session descriptions to have different count of media lines');
 }
 
-// Helper function to generate offer using a freshly created RTCPeerConnection
-// object with any audio, video, data media lines present
-function generateOffer(options={}) {
-  const {
-    audio = false,
-    video = false,
-    data = false,
-    pc,
-  } = options;
+async function generateDataChannelOffer(pc) {
+  pc.createDataChannel('test');
+  const offer = await pc.createOffer();
+  assert_equals(countApplicationLine(offer.sdp), 1, 'Expect m=application line to be present in generated SDP');
+  return offer;
+}
 
-  if (data) {
-    pc.createDataChannel('test');
-  }
-
-  const setup = {};
-
-  if (audio) {
-    setup.offerToReceiveAudio = true;
-  }
-
-  if (video) {
-    setup.offerToReceiveVideo = true;
-  }
-
-  return pc.createOffer(setup).then(offer => {
-    // Guard here to ensure that the generated offer really
-    // contain the number of media lines we want
-    const { sdp } = offer;
-
-    if(audio) {
-      assert_equals(countAudioLine(sdp), 1,
-        'Expect m=audio line to be present in generated SDP');
-    } else {
-      assert_equals(countAudioLine(sdp), 0,
-        'Expect m=audio line to be present in generated SDP');
+async function generateAudioReceiveOnlyOffer(pc)
+{
+    try {
+        pc.addTransceiver('audio', { direction: 'recvonly' });
+        return pc.createOffer();
+    } catch(e) {
+        return pc.createOffer({ offerToReceiveAudio: true });
     }
+}
 
-    if(video) {
-      assert_equals(countVideoLine(sdp), 1,
-        'Expect m=video line to be present in generated SDP');
-    } else {
-      assert_equals(countVideoLine(sdp), 0,
-        'Expect m=video line to not present in generated SDP');
+async function generateVideoReceiveOnlyOffer(pc)
+{
+    try {
+        pc.addTransceiver('video', { direction: 'recvonly' });
+        return pc.createOffer();
+    } catch(e) {
+        return pc.createOffer({ offerToReceiveVideo: true });
     }
-
-    if(data) {
-      assert_equals(countApplicationLine(sdp), 1,
-        'Expect m=application line to be present in generated SDP');
-    } else {
-      assert_equals(countApplicationLine(sdp), 0,
-        'Expect m=application line to not present in generated SDP');
-    }
-
-    return offer;
-  });
 }
 
 // Helper function to generate answer based on given offer using a freshly
 // created RTCPeerConnection object
-function generateAnswer(offer) {
+async function generateAnswer(offer) {
   const pc = new RTCPeerConnection();
-  return pc.setRemoteDescription(offer)
-  .then(() => pc.createAnswer())
-  .then((answer) => {
-    pc.close();
-    return answer;
-  });
+  await pc.setRemoteDescription(offer);
+  const answer = await pc.createAnswer();
+  pc.close();
+  return answer;
 }
 
 // Run a test function that return a promise that should
diff --git a/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-setLocalDescription-answer.html b/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-setLocalDescription-answer.html
index 4a50456f216..b783d854738 100644
--- a/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-setLocalDescription-answer.html
+++ b/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-setLocalDescription-answer.html
@@ -11,7 +11,6 @@
   // https://w3c.github.io/webrtc-pc/archives/20170605/webrtc.html
 
   // The following helper functions are called from RTCPeerConnection-helper.js:
-  //   generateOffer
   //   generateAnswer
   //   assert_session_desc_similar
 
@@ -65,7 +64,7 @@
     const states = [];
     pc.addEventListener('signalingstatechange', () => states.push(pc.signalingState));
 
-    return pc.createOffer({ offerToReceiveVideo: true })
+    return generateVideoReceiveOnlyOffer(pc)
     .then(offer =>
       pc.setRemoteDescription(offer)
       .then(() => pc.createAnswer())
@@ -97,7 +96,7 @@
 
     t.add_cleanup(() => pc.close());
 
-    return pc.createOffer({ offerToReceiveVideo: true })
+    return generateVideoReceiveOnlyOffer(pc)
     .then(offer =>
       pc.setRemoteDescription(offer)
       .then(() => pc.createAnswer())
@@ -128,7 +127,7 @@
 
     t.add_cleanup(() => pc.close());
 
-    return pc.createOffer({ offerToReceiveVideo: true })
+    return generateVideoReceiveOnlyOffer(pc)
     .then(offer =>
       pc.setRemoteDescription(offer)
       .then(() => generateAnswer(offer))
diff --git a/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-setLocalDescription-offer.html b/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-setLocalDescription-offer.html
index 9502f283f55..49eb522881a 100644
--- a/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-setLocalDescription-offer.html
+++ b/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-setLocalDescription-offer.html
@@ -11,7 +11,7 @@
   // https://w3c.github.io/webrtc-pc/archives/20170605/webrtc.html
 
   // The following helper functions are called from RTCPeerConnection-helper.js:
-  //   generateOffer
+  //   generateDataChannelOffer
   //   assert_session_desc_not_similar
   //   assert_session_desc_similar
 
@@ -62,7 +62,7 @@
     const states = [];
     pc.addEventListener('signalingstatechange', () => states.push(pc.signalingState));
 
-    return pc.createOffer({ offerToReceiveAudio: true })
+    return generateAudioReceiveOnlyOffer(pc)
     .then(offer =>
       pc.setLocalDescription(offer)
       .then(() => {
@@ -84,7 +84,7 @@
   promise_test(t => {
     const pc = new RTCPeerConnection();
     t.add_cleanup(() => pc.close());
-    return pc.createOffer({ offerToReceiveAudio: true })
+    return generateAudioReceiveOnlyOffer(pc)
     .then(offer =>
       pc.setLocalDescription({ type: 'offer' })
       .then(() => {
@@ -109,7 +109,7 @@
 
     t.add_cleanup(() => pc2.close());
 
-    return generateOffer({ pc, data: true })
+    return generateDataChannelOffer(pc)
     .then(offer =>
       promise_rejects(t, 'InvalidModificationError',
         pc2.setLocalDescription(offer)));
@@ -122,9 +122,9 @@
     // with the first offer
     const pc = new RTCPeerConnection();
     t.add_cleanup(() => pc.close());
-    return pc.createOffer({ offerToReceiveAudio: true })
+    return generateAudioReceiveOnlyOffer(pc)
     .then(offer1 =>
-      pc.createOffer({ offerToReceiveVideo: true })
+      generateVideoReceiveOnlyOffer(pc)
       .then(offer2 => {
         assert_session_desc_not_similar(offer1, offer2);
         return promise_rejects(t, 'InvalidModificationError',
@@ -139,11 +139,11 @@
     const states = [];
     pc.addEventListener('signalingstatechange', () => states.push(pc.signalingState));
 
-    return pc.createOffer({ offerToReceiveAudio: true })
+    return generateAudioReceiveOnlyOffer(pc)
     .then(offer1 =>
       pc.setLocalDescription(offer1)
       .then(() =>
-        pc.createOffer({ offerToReceiveVideo: true })
+        generateVideoReceiveOnlyOffer(pc)
         .then(offer2 =>
           pc.setLocalDescription(offer2)
           .then(offer2 => {
diff --git a/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-setLocalDescription-pranswer.html b/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-setLocalDescription-pranswer.html
index a145f95afa3..1fbb30923f3 100644
--- a/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-setLocalDescription-pranswer.html
+++ b/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-setLocalDescription-pranswer.html
@@ -11,8 +11,6 @@
   // https://w3c.github.io/webrtc-pc/archives/20170605/webrtc.html
 
   // The following helper functions are called from RTCPeerConnection-helper.js:
-  //   generateOffer
-  //   generateAnswer
   //   assert_session_desc_similar
 
   /*
@@ -86,7 +84,7 @@
     const states = [];
     pc.addEventListener('signalingstatechange', () => states.push(pc.signalingState));
 
-    return pc.createOffer({ offerToReceiveVideo: true })
+    return generateVideoReceiveOnlyOffer(pc)
     .then(offer =>
       pc.setRemoteDescription(offer)
       .then(() => pc.createAnswer())
@@ -119,7 +117,7 @@
     const states = [];
     pc.addEventListener('signalingstatechange', () => states.push(pc.signalingState));
 
-    return pc.createOffer({ offerToReceiveVideo: true })
+    return generateVideoReceiveOnlyOffer(pc)
     .then(offer =>
       pc.setRemoteDescription(offer)
       .then(() => pc.createAnswer())
@@ -141,7 +139,7 @@
     const states = [];
     pc.addEventListener('signalingstatechange', () => states.push(pc.signalingState));
 
-    return pc.createOffer({ offerToReceiveVideo: true })
+    return generateVideoReceiveOnlyOffer(pc)
     .then(offer =>
       pc.setRemoteDescription(offer)
       .then(() => pc.createAnswer())
diff --git a/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-setLocalDescription.html b/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-setLocalDescription.html
index 0ab2db1d56d..1030f494f24 100644
--- a/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-setLocalDescription.html
+++ b/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-setLocalDescription.html
@@ -11,7 +11,7 @@
   // https://w3c.github.io/webrtc-pc/archives/20170605/webrtc.html
 
   // The following helper functions are called from RTCPeerConnection-helper.js:
-  //   generateOffer
+  //   generateDataChannelOffer
   //   assert_session_desc_not_similar
   //   assert_session_desc_similar
 
@@ -50,14 +50,14 @@
     const states = [];
     pc.addEventListener('signalingstatechange', () => states.push(pc.signalingState));
 
-    return pc.createOffer({ offerToReceiveAudio: true })
+    return generateAudioReceiveOnlyOffer(pc)
     .then(offer1 =>
       pc.setLocalDescription(offer1)
       .then(() => generateAnswer(offer1))
       .then(answer => pc.setRemoteDescription(answer))
       .then(() => {
         pc.createDataChannel('test');
-        return pc.createOffer({ offerToReceiveVideo: true });
+        return generateVideoReceiveOnlyOffer(pc);
       })
       .then(offer2 =>
         pc.setLocalDescription(offer2)
@@ -79,12 +79,12 @@
     const states = [];
     pc.addEventListener('signalingstatechange', () => states.push(pc.signalingState));
 
-    return generateOffer({ pc, data: true })
+    return generateDataChannelOffer(pc)
     .then(offer => pc.setRemoteDescription(offer))
     .then(() => pc.createAnswer())
     .then(answer =>
       pc.setLocalDescription(answer)
-      .then(() => pc.createOffer({ offerToReceiveVideo: true }))
+      .then(() => generateVideoReceiveOnlyOffer(pc))
       .then(offer =>
         pc.setLocalDescription(offer)
         .then(() => {
diff --git a/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-setRemoteDescription-answer.html b/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-setRemoteDescription-answer.html
index ff554478af8..cc5bd1e0807 100644
--- a/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-setRemoteDescription-answer.html
+++ b/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-setRemoteDescription-answer.html
@@ -11,7 +11,6 @@
   // https://w3c.github.io/webrtc-pc/archives/20170605/webrtc.html
 
   // The following helper functions are called from RTCPeerConnection-helper.js:
-  //   generateOffer()
   //   generateAnswer()
   //   assert_session_desc_similar()
 
@@ -64,7 +63,7 @@
     const states = [];
     pc.addEventListener('signalingstatechange', () => states.push(pc.signalingState));
 
-    return pc.createOffer({ offerToReceiveVideo: true })
+    return generateVideoReceiveOnlyOffer(pc)
     .then(offer =>
       pc.setLocalDescription(offer)
       .then(() => generateAnswer(offer))
diff --git a/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-setRemoteDescription-pranswer.html b/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-setRemoteDescription-pranswer.html
index 9197a359671..c27ee20855b 100644
--- a/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-setRemoteDescription-pranswer.html
+++ b/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-setRemoteDescription-pranswer.html
@@ -11,7 +11,6 @@
   // https://w3c.github.io/webrtc-pc/archives/20170605/webrtc.html
 
   // The following helper functions are called from RTCPeerConnection-helper.js:
-  //   generateOffer
   //   generateAnswer
   //   assert_session_desc_similar
 
@@ -86,7 +85,7 @@
     const states = [];
     pc.addEventListener('signalingstatechange', () => states.push(pc.signalingState));
 
-    return pc.createOffer({ offerToReceiveVideo: true })
+    return generateVideoReceiveOnlyOffer(pc)
     .then(offer =>
       pc.setLocalDescription(offer)
       .then(() => generateAnswer(offer))
@@ -117,7 +116,7 @@
     const states = [];
     pc.addEventListener('signalingstatechange', () => states.push(pc.signalingState));
 
-    return pc.createOffer({ offerToReceiveVideo: true })
+    return generateVideoReceiveOnlyOffer(pc)
     .then(offer =>
       pc.setLocalDescription(offer)
       .then(() => generateAnswer(offer))
@@ -139,7 +138,7 @@
     const states = [];
     pc.addEventListener('signalingstatechange', () => states.push(pc.signalingState));
 
-    return pc.createOffer({ offerToReceiveVideo: true })
+    return generateVideoReceiveOnlyOffer(pc)
     .then(offer =>
       pc.setLocalDescription(offer)
       .then(() => generateAnswer(offer))
diff --git a/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-setRemoteDescription-rollback.html b/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-setRemoteDescription-rollback.html
index 01969dce310..ec90e561cbc 100644
--- a/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-setRemoteDescription-rollback.html
+++ b/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-setRemoteDescription-rollback.html
@@ -11,7 +11,7 @@
   // https://w3c.github.io/webrtc-pc/archives/20170605/webrtc.html
 
   // The following helper functions are called from RTCPeerConnection-helper.js:
-  //   generateOffer
+  //   generateDataChannelOffer
   //   assert_session_desc_similar
 
   /*
@@ -63,7 +63,7 @@
     const states = [];
     pc.addEventListener('signalingstatechange', () => states.push(pc.signalingState));
 
-    return generateOffer({ data: true })
+    return generateDataChannelOffer(pc)
     .then(offer => pc.setRemoteDescription(offer))
     .then(() => {
       assert_equals(pc.signalingState, 'have-remote-offer');
diff --git a/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-setRemoteDescription.html b/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-setRemoteDescription.html
index ad9cdff5fb0..182abea403e 100644
--- a/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-setRemoteDescription.html
+++ b/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-setRemoteDescription.html
@@ -91,7 +91,7 @@
       assert_equals(state, states[eventCount]);
     };
 
-    const offer = await pc.createOffer({ offerToReceiveAudio: true });
+    const offer = await generateAudioReceiveOnlyOffer(pc);
     assert_state('stable');
     await pc.setLocalDescription(offer);
     assert_state('have-local-offer');
@@ -111,10 +111,10 @@
     t.add_cleanup(() => pc.close());
     t.add_cleanup(() => pc2.close());
 
-    const offer1 = await pc2.createOffer({ offerToReceiveAudio: true });
+    const offer1 = await generateAudioReceiveOnlyOffer(pc2);
     await pc.setRemoteDescription(offer1);
     await pc.setLocalDescription(await pc.createAnswer());
-    const offer2 = await pc2.createOffer({ offerToReceiveVideo: true });
+    const offer2 = await generateVideoReceiveOnlyOffer(pc2);
     await pc.setRemoteDescription(offer2);
     assert_session_desc_not_similar(offer1, offer2);
     assert_session_desc_similar(pc.remoteDescription, offer2);
@@ -128,7 +128,7 @@
     t.add_cleanup(() => pc.close());
     t.add_cleanup(() => pc2.close());
 
-    const offer = await pc.createOffer({ offerToReceiveAudio: true });
+    const offer = await generateAudioReceiveOnlyOffer(pc);
     await pc.setLocalDescription(offer);
     await pc2.setRemoteDescription(offer);
     const answer = await pc2.createAnswer();
diff --git a/tests/wpt/web-platform-tests/webrtc/RTCRtpReceiver-getParameters.html b/tests/wpt/web-platform-tests/webrtc/RTCRtpReceiver-getParameters.html
index 97e5d10d1e5..453844d5f0e 100644
--- a/tests/wpt/web-platform-tests/webrtc/RTCRtpReceiver-getParameters.html
+++ b/tests/wpt/web-platform-tests/webrtc/RTCRtpReceiver-getParameters.html
@@ -36,7 +36,7 @@
   test(t => {
     const pc = new RTCPeerConnection();
     const { receiver } = pc.addTransceiver('audio');
-    const param = pc.getParameters();
+    const param = receiver.getParameters();
     validateReceiverRtpParameters(param);
   });
 </script>
diff --git a/tests/wpt/web-platform-tests/webrtc/RTCRtpReceiver-getStats.https.html b/tests/wpt/web-platform-tests/webrtc/RTCRtpReceiver-getStats.https.html
index 4a2e6a0bd8b..05ca9f3c90b 100644
--- a/tests/wpt/web-platform-tests/webrtc/RTCRtpReceiver-getStats.https.html
+++ b/tests/wpt/web-platform-tests/webrtc/RTCRtpReceiver-getStats.https.html
@@ -49,6 +49,12 @@
     t.add_cleanup(() => caller.close());
     const callee = new RTCPeerConnection();
     t.add_cleanup(() => callee.close());
+
+    const stream = await getNoiseStream({audio:true});
+    t.add_cleanup(() => stream.getTracks().forEach(track => track.stop()));
+    const [track] = stream.getTracks();
+    callee.addTrack(track);
+
     const { receiver } = caller.addTransceiver('audio');
 
     await doSignalingHandshake(caller, callee);
diff --git a/tests/wpt/web-platform-tests/webrtc/RTCRtpSender-getStats.https.html b/tests/wpt/web-platform-tests/webrtc/RTCRtpSender-getStats.https.html
index 18ab8255544..1af8285f4c3 100644
--- a/tests/wpt/web-platform-tests/webrtc/RTCRtpSender-getStats.https.html
+++ b/tests/wpt/web-platform-tests/webrtc/RTCRtpSender-getStats.https.html
@@ -44,7 +44,11 @@
     t.add_cleanup(() => caller.close());
     const callee = new RTCPeerConnection();
     t.add_cleanup(() => callee.close());
-    const { sender } = caller.addTransceiver('audio');
+
+    const stream = await getNoiseStream({audio:true});
+    t.add_cleanup(() => stream.getTracks().forEach(track => track.stop()));
+    const [track] = stream.getTracks();
+    const { sender } = caller.addTransceiver(track);
 
     await doSignalingHandshake(caller, callee);
     const statsReport = await sender.getStats();
diff --git a/tests/wpt/web-platform-tests/webrtc/RTCRtpTransceiver.https.html b/tests/wpt/web-platform-tests/webrtc/RTCRtpTransceiver.https.html
index 860f5de2d2a..2de9fb9f6ee 100644
--- a/tests/wpt/web-platform-tests/webrtc/RTCRtpTransceiver.https.html
+++ b/tests/wpt/web-platform-tests/webrtc/RTCRtpTransceiver.https.html
@@ -305,125 +305,6 @@
       ]);
   };
 
-  const checkAddTransceiverWithStream = async t => {
-    const pc = new RTCPeerConnection();
-    t.add_cleanup(() => pc.close());
-
-    const audioStream = await navigator.mediaDevices.getUserMedia({audio: true});
-    const videoStream = await navigator.mediaDevices.getUserMedia({video: true});
-    t.add_cleanup(() => stopTracks(audioStream, videoStream));
-
-    const audio = audioStream.getAudioTracks()[0];
-    const video = videoStream.getVideoTracks()[0];
-
-    pc.addTransceiver(audio, {streams: [audioStream]});
-    pc.addTransceiver(video, {streams: [videoStream]});
-
-    hasProps(pc.getTransceivers(),
-      [
-        {
-          receiver: {track: {kind: "audio"}},
-          sender: {track: audio},
-          direction: "sendrecv",
-          mid: null,
-          currentDirection: null,
-          stopped: false
-        },
-        {
-          receiver: {track: {kind: "video"}},
-          sender: {track: video},
-          direction: "sendrecv",
-          mid: null,
-          currentDirection: null,
-          stopped: false
-        }
-      ]);
-
-    const offer = await pc.createOffer();
-    assert_true(offer.sdp.includes("a=msid:" + audioStream.id + " " + audio.id),
-      "offer contains the expected audio msid");
-    assert_true(offer.sdp.includes("a=msid:" + videoStream.id + " " + video.id),
-      "offer contains the expected video msid");
-  };
-
-  const checkAddTransceiverWithOfferToReceive = async (t, kinds) => {
-    const pc = new RTCPeerConnection();
-    t.add_cleanup(() => pc.close());
-
-    const propsToSet = kinds.map(kind => {
-      if (kind == "audio") {
-        return "offerToReceiveAudio";
-      } else if (kind == "video") {
-        return "offerToReceiveVideo";
-      }
-    });
-
-    const options = {};
-
-    for (const prop of propsToSet) {
-      options[prop] = true;
-    }
-
-    let offer = await pc.createOffer(options);
-
-    const expected = [];
-
-    if (options.offerToReceiveAudio) {
-      expected.push(
-        {
-          receiver: {track: {kind: "audio"}},
-          sender: {track: null},
-          direction: "recvonly",
-          mid: null,
-          currentDirection: null,
-          stopped: false
-        });
-    }
-
-    if (options.offerToReceiveVideo) {
-      expected.push(
-        {
-          receiver: {track: {kind: "video"}},
-          sender: {track: null},
-          direction: "recvonly",
-          mid: null,
-          currentDirection: null,
-          stopped: false
-        });
-    }
-
-    hasProps(pc.getTransceivers(), expected);
-
-    // Test offerToReceive: false
-    for (const prop of propsToSet) {
-      options[prop] = false;
-    }
-
-    // Check that sendrecv goes to sendonly
-    for (const transceiver of pc.getTransceivers()) {
-      transceiver.direction = "sendrecv";
-    }
-
-    for (const transceiverCheck of expected) {
-      transceiverCheck.direction = "sendonly";
-    }
-
-    offer = await pc.createOffer(options);
-    hasProps(pc.getTransceivers(), expected);
-
-    // Check that recvonly goes to inactive
-    for (const transceiver of pc.getTransceivers()) {
-      transceiver.direction = "recvonly";
-    }
-
-    for (const transceiverCheck of expected) {
-      transceiverCheck.direction = "inactive";
-    }
-
-    offer = await pc.createOffer(options);
-    hasProps(pc.getTransceivers(), expected);
-  };
-
   const checkAddTransceiverWithSetRemoteOfferSending = async t => {
     const pc1 = new RTCPeerConnection();
     const pc2 = new RTCPeerConnection();
@@ -1248,70 +1129,6 @@
     assert_equals(2, countUnmuteVideo2.count, "Got 2 unmute events for pc2's video track");
   };
 
-  const checkOnAddStream = async t => {
-    const pc1 = new RTCPeerConnection();
-    t.add_cleanup(() => pc1.close());
-    const stream1 = await navigator.mediaDevices.getUserMedia({audio: true, video: true});
-    t.add_cleanup(() => stopTracks(stream1));
-    const audio1 = stream1.getAudioTracks()[0];
-    pc1.addTrack(audio1, stream1);
-    const video1 = stream1.getVideoTracks()[0];
-    pc1.addTrack(video1, stream1);
-
-    const pc2 = new RTCPeerConnection();
-    t.add_cleanup(() => pc2.close());
-    const stream2 = await navigator.mediaDevices.getUserMedia({audio: true, video: true});
-    t.add_cleanup(() => stopTracks(stream2));
-    const audio2 = stream2.getAudioTracks()[0];
-    pc2.addTrack(audio2, stream2);
-    const video2 = stream2.getVideoTracks()[0];
-    pc2.addTrack(video2, stream2);
-
-    const offer = await pc1.createOffer();
-
-    let trackEventCollector = collectTrackEvents(pc2);
-    let addstreamEventCollector = collectEvents(pc2, "addstream", e => {
-      hasProps(e, {stream: {id: stream1.id}});
-      assert_equals(e.stream.getAudioTracks().length, 1, "One audio track");
-      assert_equals(e.stream.getVideoTracks().length, 1, "One video track");
-    });
-
-    await pc2.setRemoteDescription(offer);
-
-    let addstreamEvents = addstreamEventCollector.finish();
-    assert_equals(addstreamEvents.length, 1, "Should have 1 addstream event");
-
-    let trackEvents = trackEventCollector.finish();
-
-    hasProps(trackEvents,
-      [
-        {streams: [addstreamEvents[0].stream]},
-        {streams: [addstreamEvents[0].stream]}
-      ]);
-
-    await pc1.setLocalDescription(offer);
-    const answer = await pc2.createAnswer();
-
-    trackEventCollector = collectTrackEvents(pc1);
-    addstreamEventCollector = collectEvents(pc1, "addstream", e => {
-      hasProps(e, {stream: {id: stream2.id}});
-      assert_equals(e.stream.getAudioTracks().length, 1, "One audio track");
-      assert_equals(e.stream.getVideoTracks().length, 1, "One video track");
-    });
-
-    await pc1.setRemoteDescription(answer);
-    addstreamEvents = addstreamEventCollector.finish();
-    assert_equals(addstreamEvents.length, 1, "Should have 1 addstream event");
-
-    trackEvents = trackEventCollector.finish();
-
-    hasProps(trackEvents,
-      [
-        {streams: [addstreamEvents[0].stream]},
-        {streams: [addstreamEvents[0].stream]}
-      ]);
-  };
-
   const checkStop = async t => {
     const pc1 = new RTCPeerConnection();
     t.add_cleanup(() => pc1.close());
@@ -2312,16 +2129,6 @@ const tests = [
   checkAddTransceiverWithTrack,
   checkAddTransceiverWithAddTrack,
   checkAddTransceiverWithDirection,
-  checkAddTransceiverWithStream,
-  function checkAddTransceiverWithOfferToReceiveAudio(t) {
-    return checkAddTransceiverWithOfferToReceive(t, ["audio"]);
-  },
-  function checkAddTransceiverWithOfferToReceiveVideo(t) {
-    return checkAddTransceiverWithOfferToReceive(t, ["video"]);
-  },
-  function checkAddTransceiverWithOfferToReceiveBoth(t) {
-    return checkAddTransceiverWithOfferToReceive(t, ["audio", "video"]);
-  },
   checkAddTransceiverWithSetRemoteOfferSending,
   checkAddTransceiverWithSetRemoteOfferNoSend,
   checkAddTransceiverBadKind,
@@ -2340,7 +2147,6 @@ const tests = [
   checkAddTrackExistingTransceiverThenRemove,
   checkRemoveTrackNegotiation,
   checkMute,
-  checkOnAddStream,
   checkStop,
   checkStopAfterCreateOffer,
   checkStopAfterSetLocalOffer,
diff --git a/tests/wpt/web-platform-tests/webrtc/RTCSctpTransport-constructor.html b/tests/wpt/web-platform-tests/webrtc/RTCSctpTransport-constructor.html
index c415c3fe180..7d3df051d87 100644
--- a/tests/wpt/web-platform-tests/webrtc/RTCSctpTransport-constructor.html
+++ b/tests/wpt/web-platform-tests/webrtc/RTCSctpTransport-constructor.html
@@ -11,7 +11,7 @@
   // https://w3c.github.io/webrtc-pc/archives/20170605/webrtc.html
 
   // The following helper functions are called from RTCPeerConnection-helper.js:
-  //   generateOffer()
+  //   generateDataChannelOffer()
   //   generateAnswer()
 
   /*
@@ -69,7 +69,7 @@
     t.add_cleanup(() => pc.close());
     assert_equals(pc.sctp, null);
 
-    return generateOffer({ pc, data: true })
+    return generateDataChannelOffer(pc)
     .then(offer => pc.setRemoteDescription(offer))
     .then(() => pc.createAnswer())
     .then(answer => pc.setLocalDescription(answer))
diff --git a/tests/wpt/web-platform-tests/webrtc/RTCSctpTransport-maxMessageSize.html b/tests/wpt/web-platform-tests/webrtc/RTCSctpTransport-maxMessageSize.html
index 28d17eeaccf..9163a66af15 100644
--- a/tests/wpt/web-platform-tests/webrtc/RTCSctpTransport-maxMessageSize.html
+++ b/tests/wpt/web-platform-tests/webrtc/RTCSctpTransport-maxMessageSize.html
@@ -49,7 +49,7 @@ promise_test(t => {
   assert_equals(pc.sctp, null);
   let maxMessageSize;
 
-  return generateOffer({ pc, data: true })
+  return generateDataChannelOffer(pc)
   .then((offer) => {
     assert_not_equals(mmsAttributeHelper.getValue(offer.sdp), null,
       'SDP should have max-message-size attribute');
@@ -73,7 +73,7 @@ promise_test(t => {
   t.add_cleanup(() => pc.close());
   assert_equals(pc.sctp, null);
 
-  return generateOffer({ pc, data: true })
+  return generateDataChannelOffer(pc)
   .then((offer) => {
     assert_not_equals(mmsAttributeHelper.getValue(offer.sdp), null,
       'SDP should have max-message-size attribute');
@@ -102,7 +102,7 @@ promise_test(t => {
   t.add_cleanup(() => pc.close());
   assert_equals(pc.sctp, null);
 
-  return generateOffer({ pc, data: true })
+  return generateDataChannelOffer(pc)
   .then((offer) => {
     assert_not_equals(mmsAttributeHelper.getValue(offer.sdp), null,
       'SDP should have max-message-size attribute');
@@ -124,7 +124,7 @@ promise_test(t => {
   t.add_cleanup(() => pc.close());
   assert_equals(pc.sctp, null);
 
-  return generateOffer({ pc, data: true })
+  return generateDataChannelOffer(pc)
   .then((offer) => {
     assert_not_equals(mmsAttributeHelper.getValue(offer.sdp), null,
       'SDP should have max-message-size attribute');
@@ -160,7 +160,7 @@ promise_test(t => {
   assert_equals(pc.sctp, null);
   const largerThanCanSendSize = canSendSize + 1;
 
-  return generateOffer({ pc, data: true })
+  return generateDataChannelOffer(pc)
   .then((offer) => {
     assert_not_equals(mmsAttributeHelper.getValue(offer.sdp), null,
       'SDP should have max-message-size attribute');
diff --git a/tests/wpt/web-platform-tests/webrtc/getstats.html b/tests/wpt/web-platform-tests/webrtc/getstats.html
index 937f54b74ec..053d9092ceb 100644
--- a/tests/wpt/web-platform-tests/webrtc/getstats.html
+++ b/tests/wpt/web-platform-tests/webrtc/getstats.html
@@ -38,10 +38,6 @@ This test uses data only, and thus does not require fake media devices.
     }
   });
 
-  var onRemoteStream = test.step_func(function(event) {
-    assert_unreached('WebRTC received a stream when there was none');
-  });
-
   var getStatsRecordByType = function(stats, type) {
     for (let stat of stats.values()) {
       if (stat.type == type) {
@@ -91,7 +87,6 @@ This test uses data only, and thus does not require fake media devices.
 
     gSecondConnection = new RTCPeerConnection(null);
     gSecondConnection.onicecandidate = onIceCandidateToSecond;
-    gSecondConnection.onaddstream = onRemoteStream;
 
     // The createDataChannel is necessary and sufficient to make
     // sure the ICE connection be attempted.
diff --git a/tests/wpt/web-platform-tests/webrtc/legacy/README.txt b/tests/wpt/web-platform-tests/webrtc/legacy/README.txt
new file mode 100644
index 00000000000..8adbf6aa173
--- /dev/null
+++ b/tests/wpt/web-platform-tests/webrtc/legacy/README.txt
@@ -0,0 +1,2 @@
+This directory contains files that test for behavior relevant to webrtc,
+particularly defined in https://w3c.github.io/webrtc-pc/#legacy-interface-extensions
diff --git a/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-createOffer-offerToReceive.html b/tests/wpt/web-platform-tests/webrtc/legacy/RTCPeerConnection-createOffer-offerToReceive.html
similarity index 66%
rename from tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-createOffer-offerToReceive.html
rename to tests/wpt/web-platform-tests/webrtc/legacy/RTCPeerConnection-createOffer-offerToReceive.html
index dd1827a1c8d..f710498e75f 100644
--- a/tests/wpt/web-platform-tests/webrtc/RTCPeerConnection-createOffer-offerToReceive.html
+++ b/tests/wpt/web-platform-tests/webrtc/legacy/RTCPeerConnection-createOffer-offerToReceive.html
@@ -4,10 +4,99 @@
 <link rel="help" href="https://w3c.github.io/webrtc-pc/#legacy-configuration-extensions">
 <script src="/resources/testharness.js"></script>
 <script src="/resources/testharnessreport.js"></script>
-<script src="RTCPeerConnection-helper.js"></script>
+<script src="../RTCPeerConnection-helper.js"></script>
 <script>
   'use strict';
 
+  /*
+   *  4.3.3.2 Configuration data extensions
+   *  partial dictionary RTCOfferOptions
+   */
+
+  /*
+   *  offerToReceiveAudio of type boolean
+   *    When this is given a non-false value, no outgoing track of type
+   *    "audio" is attached to the PeerConnection, and the existing
+   *    localDescription (if any) doesn't contain any sendrecv or recv
+   *    audio media sections, createOffer() will behave as if
+   *    addTransceiver("audio") had been called once prior to the createOffer() call.
+   */
+  promise_test(t => {
+    const pc = new RTCPeerConnection();
+
+    t.add_cleanup(() => pc.close());
+
+    return pc.createOffer({ offerToReceiveAudio: true })
+    .then(offer1 => {
+      assert_equals(countAudioLine(offer1.sdp), 1,
+        'Expect created offer to have audio line');
+
+      // The first createOffer implicitly calls addTransceiver('audio'),
+      // so all following offers will also have audio media section
+      // in their SDP.
+      return pc.createOffer({ offerToReceiveAudio: false })
+      .then(offer2 => {
+        assert_equals(countAudioLine(offer2.sdp), 1,
+          'Expect audio line to remain in created offer');
+      })
+    });
+  }, 'createOffer() with offerToReceiveAudio should add audio line to all subsequent created offers');
+
+  /*
+   *  offerToReceiveVideo of type boolean
+   *    When this is given a non-false value, and no outgoing track
+   *    of type "video" is attached to the PeerConnection, and the
+   *    existing localDescription (if any) doesn't contain any sendecv
+   *    or recv video media sections, createOffer() will behave as if
+   *    addTransceiver("video") had been called prior to the createOffer() call.
+   */
+  promise_test(t => {
+    const pc = new RTCPeerConnection();
+
+    t.add_cleanup(() => pc.close());
+
+    return pc.createOffer({ offerToReceiveVideo: true })
+    .then(offer1 => {
+      assert_equals(countVideoLine(offer1.sdp), 1,
+      'Expect created offer to have video line');
+
+      return pc.createOffer({ offerToReceiveVideo: false })
+      .then(offer2 => {
+        assert_equals(countVideoLine(offer2.sdp), 1,
+          'Expect video line to remain in created offer');
+      })
+    });
+  }, 'createOffer() with offerToReceiveVideo should add video line to all subsequent created offers');
+
+  promise_test(t => {
+    const pc = new RTCPeerConnection();
+
+    t.add_cleanup(() => pc.close());
+
+    return pc.createOffer({
+      offerToReceiveAudio: true,
+      offerToReceiveVideo: false
+    }).then(offer1 => {
+      assert_equals(countAudioLine(offer1.sdp), 1,
+        'Expect audio line to be found in created offer');
+
+      assert_equals(countVideoLine(offer1.sdp), 0,
+        'Expect video line to not be found in create offer');
+
+      return pc.createOffer({
+        offerToReceiveAudio: false,
+        offerToReceiveVideo: true
+      }).then(offer2 => {
+        assert_equals(countAudioLine(offer2.sdp), 1,
+          'Expect audio line to remain in created offer');
+
+        assert_equals(countVideoLine(offer2.sdp), 1,
+          'Expect video line to be found in create offer');
+      })
+    });
+  }, 'createOffer() with offerToReceiveAudio:true, then with offerToReceiveVideo:true, should have result offer with both audio and video line');
+
+
   // Run some tests for both audio and video kinds
   ['audio', 'video'].forEach((kind) => {
     const capsKind = kind[0].toUpperCase() + kind.slice(1);
diff --git a/tests/wpt/web-platform-tests/webrtc/legacy/RTCRtpTransceiver-with-OfferToReceive-options.https.html b/tests/wpt/web-platform-tests/webrtc/legacy/RTCRtpTransceiver-with-OfferToReceive-options.https.html
new file mode 100644
index 00000000000..8c2975214c4
--- /dev/null
+++ b/tests/wpt/web-platform-tests/webrtc/legacy/RTCRtpTransceiver-with-OfferToReceive-options.https.html
@@ -0,0 +1,169 @@
+<!doctype html>
+<meta charset=utf-8>
+<title>RTCRtpTransceiver with OfferToReceive legacy options</title>
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<script src="../RTCPeerConnection-helper.js"></script>
+<script>
+  'use strict';
+
+  const stopTracks = (...streams) => {
+    streams.forEach(stream => stream.getTracks().forEach(track => track.stop()));
+  };
+
+  // comparable() - produces copy of object that is JSON comparable.
+  // o = original object (required)
+  // t = template of what to examine. Useful if o is non-enumerable (optional)
+
+  const comparable = (o, t = o) => {
+    if (typeof o != 'object' || !o) {
+      return o;
+    }
+    if (Array.isArray(t) && Array.isArray(o)) {
+      return o.map((n, i) => comparable(n, t[i]));
+    }
+    return Object.keys(t).sort()
+        .reduce((r, key) => (r[key] = comparable(o[key], t[key]), r), {});
+  };
+
+  const stripKeyQuotes = s => s.replace(/"(\w+)":/g, "$1:");
+
+  const hasProps = (observed, expected) => {
+    const observable = comparable(observed, expected);
+    assert_equals(stripKeyQuotes(JSON.stringify(observable)),
+       stripKeyQuotes(JSON.stringify(comparable(expected))));
+  };
+
+  const checkAddTransceiverWithStream = async t => {
+    const pc = new RTCPeerConnection();
+    t.add_cleanup(() => pc.close());
+
+    const audioStream = await navigator.mediaDevices.getUserMedia({audio: true});
+    const videoStream = await navigator.mediaDevices.getUserMedia({video: true});
+    t.add_cleanup(() => stopTracks(audioStream, videoStream));
+
+    const audio = audioStream.getAudioTracks()[0];
+    const video = videoStream.getVideoTracks()[0];
+
+    pc.addTransceiver(audio, {streams: [audioStream]});
+    pc.addTransceiver(video, {streams: [videoStream]});
+
+    hasProps(pc.getTransceivers(),
+      [
+        {
+          receiver: {track: {kind: "audio"}},
+          sender: {track: audio},
+          direction: "sendrecv",
+          mid: null,
+          currentDirection: null,
+          stopped: false
+        },
+        {
+          receiver: {track: {kind: "video"}},
+          sender: {track: video},
+          direction: "sendrecv",
+          mid: null,
+          currentDirection: null,
+          stopped: false
+        }
+      ]);
+
+    const offer = await pc.createOffer();
+    assert_true(offer.sdp.includes("a=msid:" + audioStream.id + " " + audio.id),
+      "offer contains the expected audio msid");
+    assert_true(offer.sdp.includes("a=msid:" + videoStream.id + " " + video.id),
+      "offer contains the expected video msid");
+  };
+
+  const checkAddTransceiverWithOfferToReceive = async (t, kinds) => {
+    const pc = new RTCPeerConnection();
+    t.add_cleanup(() => pc.close());
+
+    const propsToSet = kinds.map(kind => {
+      if (kind == "audio") {
+        return "offerToReceiveAudio";
+      } else if (kind == "video") {
+        return "offerToReceiveVideo";
+      }
+    });
+
+    const options = {};
+
+    for (const prop of propsToSet) {
+      options[prop] = true;
+    }
+
+    let offer = await pc.createOffer(options);
+
+    const expected = [];
+
+    if (options.offerToReceiveAudio) {
+      expected.push(
+        {
+          receiver: {track: {kind: "audio"}},
+          sender: {track: null},
+          direction: "recvonly",
+          mid: null,
+          currentDirection: null,
+          stopped: false
+        });
+    }
+
+    if (options.offerToReceiveVideo) {
+      expected.push(
+        {
+          receiver: {track: {kind: "video"}},
+          sender: {track: null},
+          direction: "recvonly",
+          mid: null,
+          currentDirection: null,
+          stopped: false
+        });
+    }
+
+    hasProps(pc.getTransceivers(), expected);
+
+    // Test offerToReceive: false
+    for (const prop of propsToSet) {
+      options[prop] = false;
+    }
+
+    // Check that sendrecv goes to sendonly
+    for (const transceiver of pc.getTransceivers()) {
+      transceiver.direction = "sendrecv";
+    }
+
+    for (const transceiverCheck of expected) {
+      transceiverCheck.direction = "sendonly";
+    }
+
+    offer = await pc.createOffer(options);
+    hasProps(pc.getTransceivers(), expected);
+
+    // Check that recvonly goes to inactive
+    for (const transceiver of pc.getTransceivers()) {
+      transceiver.direction = "recvonly";
+    }
+
+    for (const transceiverCheck of expected) {
+      transceiverCheck.direction = "inactive";
+    }
+
+    offer = await pc.createOffer(options);
+    hasProps(pc.getTransceivers(), expected);
+  };
+
+const tests = [
+  checkAddTransceiverWithStream,
+  function checkAddTransceiverWithOfferToReceiveAudio(t) {
+    return checkAddTransceiverWithOfferToReceive(t, ["audio"]);
+  },
+  function checkAddTransceiverWithOfferToReceiveVideo(t) {
+    return checkAddTransceiverWithOfferToReceive(t, ["video"]);
+  },
+  function checkAddTransceiverWithOfferToReceiveBoth(t) {
+    return checkAddTransceiverWithOfferToReceive(t, ["audio", "video"]);
+  }
+].forEach(test => promise_test(test, test.name));
+
+</script>
diff --git a/tests/wpt/web-platform-tests/webrtc/legacy/onaddstream.https.html b/tests/wpt/web-platform-tests/webrtc/legacy/onaddstream.https.html
new file mode 100644
index 00000000000..5aa16b36a24
--- /dev/null
+++ b/tests/wpt/web-platform-tests/webrtc/legacy/onaddstream.https.html
@@ -0,0 +1,153 @@
+<!doctype html>
+<meta charset=utf-8>
+<title>onaddstream tests</title>
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<script>
+  'use strict';
+
+  const stopTracks = (...streams) => {
+    streams.forEach(stream => stream.getTracks().forEach(track => track.stop()));
+  };
+
+  const collectEvents = (target, name, check) => {
+    const events = [];
+    const handler = e => {
+      check(e);
+      events.push(e);
+    };
+
+    target.addEventListener(name, handler);
+
+    const finishCollecting = () => {
+      target.removeEventListener(name, handler);
+      return events;
+    };
+
+    return {finish: finishCollecting};
+  };
+
+  const collectAddTrackEvents = stream => {
+    const checkEvent = e => {
+      assert_true(e.track instanceof MediaStreamTrack, "Track is set on event");
+      assert_true(stream.getTracks().includes(e.track),
+        "track in addtrack event is in the stream");
+    };
+    return collectEvents(stream, "addtrack", checkEvent);
+  };
+
+  const collectRemoveTrackEvents = stream => {
+    const checkEvent = e => {
+      assert_true(e.track instanceof MediaStreamTrack, "Track is set on event");
+      assert_true(!stream.getTracks().includes(e.track),
+        "track in removetrack event is not in the stream");
+    };
+    return collectEvents(stream, "removetrack", checkEvent);
+  };
+
+  const collectTrackEvents = pc => {
+    const checkEvent = e => {
+      assert_true(e.track instanceof MediaStreamTrack, "Track is set on event");
+      assert_true(e.receiver instanceof RTCRtpReceiver, "Receiver is set on event");
+      assert_true(e.transceiver instanceof RTCRtpTransceiver, "Transceiver is set on event");
+      assert_true(Array.isArray(e.streams), "Streams is set on event");
+      e.streams.forEach(stream => {
+        assert_true(stream.getTracks().includes(e.track),
+           "Each stream in event contains the track");
+      });
+      assert_equals(e.receiver, e.transceiver.receiver,
+                    "Receiver belongs to transceiver");
+      assert_equals(e.track, e.receiver.track,
+                    "Track belongs to receiver");
+    };
+
+    return collectEvents(pc, "track", checkEvent);
+  };
+
+  // comparable() - produces copy of object that is JSON comparable.
+  // o = original object (required)
+  // t = template of what to examine. Useful if o is non-enumerable (optional)
+
+  const comparable = (o, t = o) => {
+    if (typeof o != 'object' || !o) {
+      return o;
+    }
+    if (Array.isArray(t) && Array.isArray(o)) {
+      return o.map((n, i) => comparable(n, t[i]));
+    }
+    return Object.keys(t).sort()
+        .reduce((r, key) => (r[key] = comparable(o[key], t[key]), r), {});
+  };
+
+  const stripKeyQuotes = s => s.replace(/"(\w+)":/g, "$1:");
+
+  const hasProps = (observed, expected) => {
+    const observable = comparable(observed, expected);
+    assert_equals(stripKeyQuotes(JSON.stringify(observable)),
+       stripKeyQuotes(JSON.stringify(comparable(expected))));
+  };
+
+  promise_test(async t => {
+    const pc1 = new RTCPeerConnection();
+    t.add_cleanup(() => pc1.close());
+    const stream1 = await navigator.mediaDevices.getUserMedia({audio: true, video: true});
+    t.add_cleanup(() => stopTracks(stream1));
+    const audio1 = stream1.getAudioTracks()[0];
+    pc1.addTrack(audio1, stream1);
+    const video1 = stream1.getVideoTracks()[0];
+    pc1.addTrack(video1, stream1);
+
+    const pc2 = new RTCPeerConnection();
+    t.add_cleanup(() => pc2.close());
+    const stream2 = await navigator.mediaDevices.getUserMedia({audio: true, video: true});
+    t.add_cleanup(() => stopTracks(stream2));
+    const audio2 = stream2.getAudioTracks()[0];
+    pc2.addTrack(audio2, stream2);
+    const video2 = stream2.getVideoTracks()[0];
+    pc2.addTrack(video2, stream2);
+
+    const offer = await pc1.createOffer();
+
+    let trackEventCollector = collectTrackEvents(pc2);
+    let addstreamEventCollector = collectEvents(pc2, "addstream", e => {
+      hasProps(e, {stream: {id: stream1.id}});
+      assert_equals(e.stream.getAudioTracks().length, 1, "One audio track");
+      assert_equals(e.stream.getVideoTracks().length, 1, "One video track");
+    });
+
+    await pc2.setRemoteDescription(offer);
+
+    let addstreamEvents = addstreamEventCollector.finish();
+    assert_equals(addstreamEvents.length, 1, "Should have 1 addstream event");
+
+    let trackEvents = trackEventCollector.finish();
+
+    hasProps(trackEvents,
+      [
+        {streams: [addstreamEvents[0].stream]},
+        {streams: [addstreamEvents[0].stream]}
+      ]);
+
+    await pc1.setLocalDescription(offer);
+    const answer = await pc2.createAnswer();
+
+    trackEventCollector = collectTrackEvents(pc1);
+    addstreamEventCollector = collectEvents(pc1, "addstream", e => {
+      hasProps(e, {stream: {id: stream2.id}});
+      assert_equals(e.stream.getAudioTracks().length, 1, "One audio track");
+      assert_equals(e.stream.getVideoTracks().length, 1, "One video track");
+    });
+
+    await pc1.setRemoteDescription(answer);
+    addstreamEvents = addstreamEventCollector.finish();
+    assert_equals(addstreamEvents.length, 1, "Should have 1 addstream event");
+
+    trackEvents = trackEventCollector.finish();
+
+    hasProps(trackEvents,
+      [
+        {streams: [addstreamEvents[0].stream]},
+        {streams: [addstreamEvents[0].stream]}
+      ]);
+  },"Check onaddstream");
+</script>
diff --git a/tests/wpt/web-platform-tests/webrtc/no-media-call.html b/tests/wpt/web-platform-tests/webrtc/no-media-call.html
index 8f4f5962d4a..0f2e2a33e62 100644
--- a/tests/wpt/web-platform-tests/webrtc/no-media-call.html
+++ b/tests/wpt/web-platform-tests/webrtc/no-media-call.html
@@ -17,6 +17,7 @@ This test uses the legacy callback API with no media, and thus does not require
   <!-- These files are in place when executing on W3C. -->
   <script src="/resources/testharness.js"></script>
   <script src="/resources/testharnessreport.js"></script>
+  <script src="/webrtc/RTCPeerConnection-helper.js"></script>
   <script type="text/javascript">
   var test = async_test('Can set up a basic WebRTC call with no data.');
 
@@ -123,9 +124,7 @@ This test uses the legacy callback API with no media, and thus does not require
     gSecondConnection.onicecandidate = onIceCandidateToSecond;
     gSecondConnection.oniceconnectionstatechange = onIceConnectionStateChange;
 
-    // The offerToReceiveVideo is necessary and sufficient to make
-    // an actual connection.
-    gFirstConnection.createOffer({offerToReceiveVideo: true})
+    generateVideoReceiveOnlyOffer(gFirstConnection)
       .then(onOfferCreated, failed('createOffer'));
   });
 </script>
diff --git a/tests/wpt/web-platform-tests/webrtc/protocol/jsep-initial-offer.https.html b/tests/wpt/web-platform-tests/webrtc/protocol/jsep-initial-offer.https.html
new file mode 100644
index 00000000000..88bdfcfc286
--- /dev/null
+++ b/tests/wpt/web-platform-tests/webrtc/protocol/jsep-initial-offer.https.html
@@ -0,0 +1,35 @@
+<!doctype html>
+<meta charset=utf-8>
+<title>RTCPeerConnection.prototype.createOffer</title>
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<script src="../RTCPeerConnection-helper.js"></script>
+<script>
+  'use strict';
+
+  // Tests for the construction of initial offers according to
+  // draft-ietf-rtcweb-jsep-24 section 5.2.1
+  promise_test(async t => {
+    const pc = new RTCPeerConnection();
+    const offer = await generateVideoReceiveOnlyOffer(pc);
+    let offer_lines = offer.sdp.split('\r\n');
+    // The first 3 lines are dictated by JSEP.
+    assert_equals(offer_lines[0], "v=0");
+    assert_equals(offer_lines[1].slice(0, 2), "o=");
+    // JSEP says that the address part SHOULD be a meaningless address
+    // "such as" IN IP4 127.0.0.1. We do strict matching here in order
+    // to detect if anyone ever uses something different.
+    assert_regexp_match(offer_lines[1], /^o=- \d+ \d+ IN IP4 127.0.0.1$/);
+    const fields = RegExp(/^o=- (\d+) (\d+)/).exec(offer_lines[1]);
+    // Per RFC 3264, the sess-id should be representable in an uint64
+    // Note: JSEP -24 has this wrong - see bug:
+    // https://github.com/rtcweb-wg/jsep/issues/855
+    assert_less_than(Number(fields[1]), 2**64);
+    // Per RFC 3264, the version should be less than 2^62 to avoid overflow
+    assert_less_than(Number(fields[2]), 2**62);
+    // Note: using - in s=- is a SHOULD in JSEP, not a MUST.
+    assert_equals(offer_lines[2], "s=-");
+    // After this, the order is not dictated by JSEP.
+    // TODO: Check lines subsequent to the s= line.
+  }, 'Offer conforms to basic SDP requirements');
+</script>
diff --git a/tests/wpt/web-platform-tests/webrtc/protocol/video-codecs.https.html b/tests/wpt/web-platform-tests/webrtc/protocol/video-codecs.https.html
index 547856f2a27..e728effbeb9 100644
--- a/tests/wpt/web-platform-tests/webrtc/protocol/video-codecs.https.html
+++ b/tests/wpt/web-platform-tests/webrtc/protocol/video-codecs.https.html
@@ -21,7 +21,7 @@
 // Section 5: Browsers MUST implement VP8 and H.264 Constrained Baseline
 promise_test(async t => {
   const pc = new RTCPeerConnection();
-  const offer = await pc.createOffer({offerToReceiveVideo: true});
+  const offer = await generateVideoReceiveOnlyOffer(pc);
   let video_section_found = false;
   for (let section of offer.sdp.split(/\r\nm=/)) {
     if (section.search('video') != 0) {