diff --git a/tests/wpt/metadata-layout-2020/FileAPI/url/url-in-tags-revoke.window.js.ini b/tests/wpt/metadata-layout-2020/FileAPI/url/url-in-tags-revoke.window.js.ini
index 76b44d9e9cf..3605e8f3fc9 100644
--- a/tests/wpt/metadata-layout-2020/FileAPI/url/url-in-tags-revoke.window.js.ini
+++ b/tests/wpt/metadata-layout-2020/FileAPI/url/url-in-tags-revoke.window.js.ini
@@ -4,7 +4,7 @@
     expected: TIMEOUT
 
   [Opening a blob URL in a new window immediately before revoking it works.]
-    expected: FAIL
+    expected: TIMEOUT
 
   [Fetching a blob URL immediately before revoking it works in an iframe.]
     expected: FAIL
diff --git a/tests/wpt/metadata-layout-2020/css/CSS2/floats/hit-test-floats-002.html.ini b/tests/wpt/metadata-layout-2020/css/CSS2/floats/hit-test-floats-002.html.ini
new file mode 100644
index 00000000000..f64b45fea6b
--- /dev/null
+++ b/tests/wpt/metadata-layout-2020/css/CSS2/floats/hit-test-floats-002.html.ini
@@ -0,0 +1,4 @@
+[hit-test-floats-002.html]
+  [Hit test float]
+    expected: FAIL
+
diff --git a/tests/wpt/metadata-layout-2020/css/css-transforms/transform-scale-hittest.html.ini b/tests/wpt/metadata-layout-2020/css/css-transforms/transform-scale-hittest.html.ini
index 4a1e8110f6f..f8e7e539aae 100644
--- a/tests/wpt/metadata-layout-2020/css/css-transforms/transform-scale-hittest.html.ini
+++ b/tests/wpt/metadata-layout-2020/css/css-transforms/transform-scale-hittest.html.ini
@@ -2,3 +2,6 @@
   [Hit test intersecting scaled box]
     expected: FAIL
 
+  [Hit test within unscaled box]
+    expected: FAIL
+
diff --git a/tests/wpt/metadata-layout-2020/css/css-transitions/no-transition-from-ua-to-blocking-stylesheet.html.ini b/tests/wpt/metadata-layout-2020/css/css-transitions/no-transition-from-ua-to-blocking-stylesheet.html.ini
index e35a452a186..70a00a101f6 100644
--- a/tests/wpt/metadata-layout-2020/css/css-transitions/no-transition-from-ua-to-blocking-stylesheet.html.ini
+++ b/tests/wpt/metadata-layout-2020/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-layout-2020/css/cssom-view/elementFromPoint-001.html.ini b/tests/wpt/metadata-layout-2020/css/cssom-view/elementFromPoint-001.html.ini
deleted file mode 100644
index e38782d8c85..00000000000
--- a/tests/wpt/metadata-layout-2020/css/cssom-view/elementFromPoint-001.html.ini
+++ /dev/null
@@ -1,4 +0,0 @@
-[elementFromPoint-001.html]
-  [CSSOM View - 5 - extensions to the Document interface]
-    expected: FAIL
-
diff --git a/tests/wpt/metadata-layout-2020/css/cssom-view/elementFromPosition.html.ini b/tests/wpt/metadata-layout-2020/css/cssom-view/elementFromPosition.html.ini
index c131078eace..23c61ede1a1 100644
--- a/tests/wpt/metadata-layout-2020/css/cssom-view/elementFromPosition.html.ini
+++ b/tests/wpt/metadata-layout-2020/css/cssom-view/elementFromPosition.html.ini
@@ -17,3 +17,6 @@
   [test the top of layer]
     expected: FAIL
 
+  [test some point of the element: top left corner]
+    expected: FAIL
+
diff --git a/tests/wpt/metadata-layout-2020/css/cssom-view/elementsFromPoint-invalid-cases.html.ini b/tests/wpt/metadata-layout-2020/css/cssom-view/elementsFromPoint-invalid-cases.html.ini
new file mode 100644
index 00000000000..e181af5397f
--- /dev/null
+++ b/tests/wpt/metadata-layout-2020/css/cssom-view/elementsFromPoint-invalid-cases.html.ini
@@ -0,0 +1,4 @@
+[elementsFromPoint-invalid-cases.html]
+  [The root element is the last element returned for otherwise empty queries within the viewport]
+    expected: FAIL
+
diff --git a/tests/wpt/metadata-layout-2020/css/cssom/cssstyledeclaration-csstext.html.ini b/tests/wpt/metadata-layout-2020/css/cssom/cssstyledeclaration-csstext.html.ini
new file mode 100644
index 00000000000..c6715d49f44
--- /dev/null
+++ b/tests/wpt/metadata-layout-2020/css/cssom/cssstyledeclaration-csstext.html.ini
@@ -0,0 +1,4 @@
+[cssstyledeclaration-csstext.html]
+  [cssText on computed style declaration returns the empty string]
+    expected: FAIL
+
diff --git a/tests/wpt/metadata-layout-2020/css/cssom/cssstyledeclaration-custom-properties.html.ini b/tests/wpt/metadata-layout-2020/css/cssom/cssstyledeclaration-custom-properties.html.ini
new file mode 100644
index 00000000000..595199d7d35
--- /dev/null
+++ b/tests/wpt/metadata-layout-2020/css/cssom/cssstyledeclaration-custom-properties.html.ini
@@ -0,0 +1,4 @@
+[cssstyledeclaration-custom-properties.html]
+  [Custom properties are included in computed style]
+    expected: FAIL
+
diff --git a/tests/wpt/metadata-layout-2020/css/filter-effects/fecomposite-non-zero-inoffset-001.html.ini b/tests/wpt/metadata-layout-2020/css/filter-effects/fecomposite-non-zero-inoffset-001.html.ini
new file mode 100644
index 00000000000..055c56143e6
--- /dev/null
+++ b/tests/wpt/metadata-layout-2020/css/filter-effects/fecomposite-non-zero-inoffset-001.html.ini
@@ -0,0 +1,2 @@
+[fecomposite-non-zero-inoffset-001.html]
+  expected: FAIL
diff --git a/tests/wpt/metadata-layout-2020/fetch/content-type/response.window.js.ini b/tests/wpt/metadata-layout-2020/fetch/content-type/response.window.js.ini
index 18aea709ba7..6adf3645101 100644
--- a/tests/wpt/metadata-layout-2020/fetch/content-type/response.window.js.ini
+++ b/tests/wpt/metadata-layout-2020/fetch/content-type/response.window.js.ini
@@ -312,21 +312,21 @@
   [Response: combined response Content-Type: text/html;" \\" text/plain ";charset=GBK]
     expected: NOTRUN
 
-  [<iframe>: separate response Content-Type: text/html;" text/plain]
-    expected: FAIL
-
   [<iframe>: separate response Content-Type: text/html */*;charset=gbk]
     expected: FAIL
 
   [<iframe>: combined response Content-Type: text/html;" \\" text/plain]
     expected: FAIL
 
-  [<iframe>: combined response Content-Type: text/html;charset=gbk text/plain text/html]
-    expected: FAIL
-
-  [<iframe>: separate response Content-Type: text/html */*]
-    expected: FAIL
-
   [<iframe>: combined response Content-Type: text/html;x=" text/plain]
     expected: FAIL
 
+  [<iframe>: combined response Content-Type: text/html;" text/plain]
+    expected: FAIL
+
+  [<iframe>: combined response Content-Type: */* text/html]
+    expected: FAIL
+
+  [<iframe>: separate response Content-Type: text/plain */*]
+    expected: FAIL
+
diff --git a/tests/wpt/metadata-layout-2020/fetch/content-type/script.window.js.ini b/tests/wpt/metadata-layout-2020/fetch/content-type/script.window.js.ini
index d2df9b78483..b2ffc8abf78 100644
--- a/tests/wpt/metadata-layout-2020/fetch/content-type/script.window.js.ini
+++ b/tests/wpt/metadata-layout-2020/fetch/content-type/script.window.js.ini
@@ -56,3 +56,6 @@
   [separate text/javascript x/x]
     expected: FAIL
 
+  [separate text/javascript error]
+    expected: FAIL
+
diff --git a/tests/wpt/metadata-layout-2020/fetch/nosniff/parsing-nosniff.window.js.ini b/tests/wpt/metadata-layout-2020/fetch/nosniff/parsing-nosniff.window.js.ini
index d4ba399b762..87c807a49ff 100644
--- a/tests/wpt/metadata-layout-2020/fetch/nosniff/parsing-nosniff.window.js.ini
+++ b/tests/wpt/metadata-layout-2020/fetch/nosniff/parsing-nosniff.window.js.ini
@@ -11,6 +11,3 @@
   [X-Content-Type-Options%3A%20nosniff%0C]
     expected: FAIL
 
-  [X-Content-Type-Options%3A%20'NosniFF']
-    expected: FAIL
-
diff --git a/tests/wpt/metadata-layout-2020/html/browsers/history/the-history-interface/traverse_the_history_5.html.ini b/tests/wpt/metadata-layout-2020/html/browsers/history/the-history-interface/traverse_the_history_3.html.ini
similarity index 71%
rename from tests/wpt/metadata-layout-2020/html/browsers/history/the-history-interface/traverse_the_history_5.html.ini
rename to tests/wpt/metadata-layout-2020/html/browsers/history/the-history-interface/traverse_the_history_3.html.ini
index dc2e45516de..51f8272a6de 100644
--- a/tests/wpt/metadata-layout-2020/html/browsers/history/the-history-interface/traverse_the_history_5.html.ini
+++ b/tests/wpt/metadata-layout-2020/html/browsers/history/the-history-interface/traverse_the_history_3.html.ini
@@ -1,4 +1,4 @@
-[traverse_the_history_5.html]
+[traverse_the_history_3.html]
   [Multiple history traversals, last would be aborted]
     expected: FAIL
 
diff --git a/tests/wpt/metadata-layout-2020/html/interaction/focus/the-autofocus-attribute/supported-elements.html.ini b/tests/wpt/metadata-layout-2020/html/interaction/focus/the-autofocus-attribute/supported-elements.html.ini
index af14e19a466..c9d963b55d2 100644
--- a/tests/wpt/metadata-layout-2020/html/interaction/focus/the-autofocus-attribute/supported-elements.html.ini
+++ b/tests/wpt/metadata-layout-2020/html/interaction/focus/the-autofocus-attribute/supported-elements.html.ini
@@ -7,7 +7,7 @@
     expected: NOTRUN
 
   [Element with tabindex should support autofocus]
-    expected: TIMEOUT
+    expected: FAIL
 
   [Area element should support autofocus]
     expected: NOTRUN
@@ -16,5 +16,5 @@
     expected: NOTRUN
 
   [Non-HTMLElement should not support autofocus]
-    expected: NOTRUN
+    expected: TIMEOUT
 
diff --git a/tests/wpt/metadata-layout-2020/html/semantics/embedded-content/the-iframe-element/iframe_sandbox_popups_nonescaping-3.html.ini b/tests/wpt/metadata-layout-2020/html/semantics/embedded-content/the-iframe-element/iframe_sandbox_popups_nonescaping-3.html.ini
index f4f994c5d6f..7a36937927c 100644
--- a/tests/wpt/metadata-layout-2020/html/semantics/embedded-content/the-iframe-element/iframe_sandbox_popups_nonescaping-3.html.ini
+++ b/tests/wpt/metadata-layout-2020/html/semantics/embedded-content/the-iframe-element/iframe_sandbox_popups_nonescaping-3.html.ini
@@ -1,5 +1,4 @@
 [iframe_sandbox_popups_nonescaping-3.html]
-  expected: TIMEOUT
   [Check that popups from a sandboxed iframe do not escape the sandbox]
-    expected: NOTRUN
+    expected: FAIL
 
diff --git a/tests/wpt/metadata-layout-2020/html/webappapis/scripting/processing-model-2/integration-with-the-javascript-job-queue/promise-job-entry.html.ini b/tests/wpt/metadata-layout-2020/html/webappapis/scripting/processing-model-2/integration-with-the-javascript-job-queue/promise-job-entry.html.ini
index d16e3ccb769..a1effd5f801 100644
--- a/tests/wpt/metadata-layout-2020/html/webappapis/scripting/processing-model-2/integration-with-the-javascript-job-queue/promise-job-entry.html.ini
+++ b/tests/wpt/metadata-layout-2020/html/webappapis/scripting/processing-model-2/integration-with-the-javascript-job-queue/promise-job-entry.html.ini
@@ -1,5 +1,4 @@
 [promise-job-entry.html]
-  expected: TIMEOUT
   [Fulfillment handler on fulfilled promise]
     expected: FAIL
 
@@ -16,5 +15,5 @@
     expected: FAIL
 
   [Fulfillment handler on pending-then-fulfilled promise]
-    expected: TIMEOUT
+    expected: FAIL
 
diff --git a/tests/wpt/metadata-layout-2020/webaudio/the-audio-api/the-audiobuffersourcenode-interface/audiobuffersource-multi-channels.html.ini b/tests/wpt/metadata-layout-2020/webaudio/the-audio-api/the-audiobuffersourcenode-interface/audiobuffersource-multi-channels.html.ini
index 84787faa62f..77032256502 100644
--- a/tests/wpt/metadata-layout-2020/webaudio/the-audio-api/the-audiobuffersourcenode-interface/audiobuffersource-multi-channels.html.ini
+++ b/tests/wpt/metadata-layout-2020/webaudio/the-audio-api/the-audiobuffersourcenode-interface/audiobuffersource-multi-channels.html.ini
@@ -74,3 +74,6 @@
   [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 44065 more errors.\n\tMax AbsError of 1.9986611604690552e+0 at index of 15080.\n\t[15080\]\t-9.9994289875030518e-1\t9.9871826171875000e-1\t1.9986611604690552e+0\t2.0012262087101997e+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 44059 more errors.\n\tMax AbsError of 1.9986611604690552e+0 at index of 17285.\n\t[17285\]\t-9.9994289875030518e-1\t9.9871826171875000e-1\t1.9986611604690552e+0\t2.0012262087101997e+0\t3.0517578125000000e-5\n\tMax RelError of Infinity at index of 12348.\n\t[12348\]\t9.5105654001235962e-1\t0.0000000000000000e+0\t9.5105654001235962e-1\tInfinity\t3.0517578125000000e-5\n]
+    expected: FAIL
+
diff --git a/tests/wpt/metadata-layout-2020/webaudio/the-audio-api/the-audiobuffersourcenode-interface/sub-sample-buffer-stitching.html.ini b/tests/wpt/metadata-layout-2020/webaudio/the-audio-api/the-audiobuffersourcenode-interface/sub-sample-buffer-stitching.html.ini
index 442dc0ed53f..b105dc0821e 100644
--- a/tests/wpt/metadata-layout-2020/webaudio/the-audio-api/the-audiobuffersourcenode-interface/sub-sample-buffer-stitching.html.ini
+++ b/tests/wpt/metadata-layout-2020/webaudio/the-audio-api/the-audiobuffersourcenode-interface/sub-sample-buffer-stitching.html.ini
@@ -122,3 +122,9 @@
   [X Stitched sine-wave buffers at sample rate 44100 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":0.000090957,"relativeThreshold":0}.\n\tIndex\tActual\t\t\tExpected\t\tAbsError\t\tRelError\t\tTest threshold\n\t[31080\]\t-6.7816996732928000e+14\t5.6332010030746460e-1\t6.7816996732928063e+14\t1.2038802928550393e+15\t9.0957000000000003e-5\n\t[31081\]\t4.5854689648100989e-41\t6.1397600173950195e-1\t6.1397600173950195e-1\t1.0000000000000000e+0\t9.0957000000000003e-5\n\tMax AbsError of 6.7816996732928063e+14 at index of 31080.\n\tMax RelError of 1.2038802928550393e+15 at index of 31080.\n]
     expected: FAIL
 
+  [X SNR (45.01863889941501 dB) is not greater than or equal to 85.58. Got 45.01863889941501.]
+    expected: FAIL
+
+  [X Stitched sine-wave buffers at sample rate 44100 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":0.000090957,"relativeThreshold":0}.\n\tIndex\tActual\t\t\tExpected\t\tAbsError\t\tRelError\t\tTest threshold\n\t[31080\]\t5.6092996914003379e-10\t5.6332010030746460e-1\t5.6332009974653463e-1\t9.9999999900424297e-1\t9.0957000000000003e-5\n\t[31081\]\t4.5875709125065861e-41\t6.1397600173950195e-1\t6.1397600173950195e-1\t1.0000000000000000e+0\t9.0957000000000003e-5\n\tMax AbsError of 6.1397600173950195e-1 at index of 31081.\n\tMax RelError of 1.0000000000000000e+0 at index of 31081.\n]
+    expected: FAIL
+
diff --git a/tests/wpt/metadata/FileAPI/url/url-in-tags-revoke.window.js.ini b/tests/wpt/metadata/FileAPI/url/url-in-tags-revoke.window.js.ini
index d4f62ed7113..faa00f45ecf 100644
--- a/tests/wpt/metadata/FileAPI/url/url-in-tags-revoke.window.js.ini
+++ b/tests/wpt/metadata/FileAPI/url/url-in-tags-revoke.window.js.ini
@@ -7,7 +7,7 @@
     expected: FAIL
 
   [Opening a blob URL in a new window immediately before revoking it works.]
-    expected: FAIL
+    expected: TIMEOUT
 
   [Opening a blob URL in a noopener about:blank window immediately before revoking it works.]
     expected: TIMEOUT
diff --git a/tests/wpt/metadata/MANIFEST.json b/tests/wpt/metadata/MANIFEST.json
index af4e0236a06..799e611fae3 100644
--- a/tests/wpt/metadata/MANIFEST.json
+++ b/tests/wpt/metadata/MANIFEST.json
@@ -61,6 +61,20 @@
      ]
     },
     "css-flexbox": {
+     "negative-flex-margins-crash.html": [
+      "8bcc566c0f702ef6a8e581bb6790476c71f19bcb",
+      [
+       null,
+       {}
+      ]
+     ],
+     "negative-flex-rounding-crash.html": [
+      "ad69cc059ec705a9856f2c170827b9df18f1662c",
+      [
+       null,
+       {}
+      ]
+     ],
      "padding-overflow-crash.html": [
       "fd0c333fabadb073b9977a63de6a8c5c3ed79042",
       [
@@ -143793,6 +143807,32 @@
         {}
        ]
       ],
+      "grid-layout-stale-001.html": [
+       "bb81546678cea67020c2f46a470098d6454981d9",
+       [
+        null,
+        [
+         [
+          "/css/css-grid/grid-model/reference/grid-layout-stale-001-ref.html",
+          "=="
+         ]
+        ],
+        {}
+       ]
+      ],
+      "grid-layout-stale-002.html": [
+       "ea11cd5c5cb5e869493adb908892c3b8f8d7c35d",
+       [
+        null,
+        [
+         [
+          "/css/css-grid/grid-model/reference/grid-layout-stale-002-ref.html",
+          "=="
+         ]
+        ],
+        {}
+       ]
+      ],
       "grid-margins-no-collapse-001.html": [
        "764cca9ced0077a7376b506f3ef8ca39d8072202",
        [
@@ -203865,6 +203905,19 @@
        {}
       ]
      ],
+     "fecomposite-non-zero-inoffset-001.html": [
+      "b2d71cfa981a4a93b0fa9ad0c41d9351c2889956",
+      [
+       null,
+       [
+        [
+         "/css/filter-effects/reference/fecomposite-non-zero-inoffset-001-ref.html",
+         "=="
+        ]
+       ],
+       {}
+      ]
+     ],
      "filter-cb-abspos-inline-001.html": [
       "6f99c48d5f34761ba1bc1ce7dbdfd927469ac65a",
       [
@@ -204372,6 +204425,19 @@
        {}
       ]
      ],
+     "remove-filter-repaint.html": [
+      "a9af9db34eeaf10235521514f8c17ceca858924e",
+      [
+       null,
+       [
+        [
+         "/css/filter-effects/reference/remove-filter-repaint-ref.html",
+         "=="
+        ]
+       ],
+       {}
+      ]
+     ],
      "root-element-with-opacity-filter-001.html": [
       "577e2bd4c032799a159c1c7542812e66081bfcea",
       [
@@ -263055,6 +263121,12 @@
      }
     }
    },
+   "contenteditable": {
+    "META.yml": [
+     "3618b8d29d08c2315f6480c0e02578bb4784b344",
+     []
+    ]
+   },
    "cookie-store": {
     "META.yml": [
      "46da8a9fb654cc685e1ba928d2b7adef9c20d4c8",
@@ -294272,6 +294344,14 @@
        "100x100-grey-box.html": [
         "0592f6d2ce582c3c89b9d7f5278eed9458531c3c",
         []
+       ],
+       "grid-layout-stale-001-ref.html": [
+        "3ade075c99cc2009aabc018aa4181b0ff930bea3",
+        []
+       ],
+       "grid-layout-stale-002-ref.html": [
+        "5d4d996106d13a060cf192efb134e1c74aae024d",
+        []
        ]
       }
      },
@@ -308288,6 +308368,10 @@
        "cf2c997f6c0d60cac9896c0b0014189cea7790bc",
        []
       ],
+      "fecomposite-non-zero-inoffset-001-ref.html": [
+       "e4900ad0476a208ec82950a80fb36d1481bd8c09",
+       []
+      ],
       "filter-effect-remove-unattached-ref.html": [
        "5f9f7a76ec71bfa5abe4a0a82bc126af8fa0ad5a",
        []
@@ -308332,6 +308416,10 @@
        "91326ef585e6910cd499ad2d6650f18fca486921",
        []
       ],
+      "remove-filter-repaint-ref.html": [
+       "bde2a93360b62fcf877c270815f252b5ea0c3191",
+       []
+      ],
       "root-element-with-opacity-filter-001-ref.html": [
        "cd16e54c8e5b73b02585c606d0133bb36c821b31",
        []
@@ -346994,7 +347082,7 @@
         []
        ],
        "keys.py": [
-        "d4072f5a3f33d8422825e1fdc4f017ed7d79993b",
+        "26825f04148befabc9a7b6ae71f1d8313a437e38",
         []
        ],
        "mouse.py": [
@@ -347075,11 +347163,11 @@
        []
       ],
       "asserts.py": [
-       "f65137463b48f94fd0c5f2383b1a7c35bcd1de54",
+       "5bd7f5b38e7a344fb2a1f7c40090fb5edd28c4d4",
        []
       ],
       "authentication.py": [
-       "6f880f3c85165295bf9e98aa4e4adba2eca88cbd",
+       "1e88a9e730d0805f8e6562a2dae7829b4baa349c",
        []
       ],
       "defaults.py": [
@@ -347087,7 +347175,7 @@
        []
       ],
       "fixtures.py": [
-       "ab2aaf4e75d96492d9c6419ab11d567205652b8f",
+       "80ccfddf3d15ad739f7eca6a77fac79e2dcdcaef",
        []
       ],
       "helpers.py": [
@@ -347095,15 +347183,15 @@
        []
       ],
       "http_request.py": [
-       "5e46d97017e14ba009d4d1ed6d62bb5012f48d15",
+       "895d1319ac0ac8b9a63defcb73f303c4a31e80bd",
        []
       ],
       "image.py": [
-       "81dd933943f78b4bad69967c26729b70b992acb6",
+       "6149ccccbe3252e5c1c2bc37ba3dd3103ffbf9b6",
        []
       ],
       "inline.py": [
-       "b65b9cb8b11d27ee4c947a5c2ba5b59cd3853c78",
+       "15bc26e54c68d4ce7c76133f597f4da50eb2e298",
        []
       ],
       "merge_dictionaries.py": [
@@ -350038,7 +350126,7 @@
       []
      ],
      "webxr_test_constants_fake_world.js": [
-      "4e2adc633fd88bc13a4ab62bee86b4f3fbd19479",
+      "7e428e21550f6a52461cb8470dee0aa44e3f4578",
       []
      ],
      "webxr_util.js": [
@@ -377712,6 +377800,15 @@
      ]
     }
    },
+   "contenteditable": {
+    "plaintext-only.html": [
+     "cb8308edcc49a98be5c34c9614bc61b69e44f784",
+     [
+      null,
+      {}
+     ]
+    ]
+   },
    "cookie-store": {
     "change_eventhandler_for_document_cookie.tentative.https.window.js": [
      "0a8b1bd21efc9b0ac69468ad81c306757e5b18ff",
@@ -382417,6 +382514,41 @@
        null,
        {}
       ]
+     ],
+     "revert-val-006.html": [
+      "2b238f6d7e53b35cbdfe98c1fcac3625b9cfd72e",
+      [
+       null,
+       {}
+      ]
+     ],
+     "revert-val-007.html": [
+      "38078fcfa9ad2a064ead3a2e30db3d6790d265be",
+      [
+       null,
+       {}
+      ]
+     ],
+     "revert-val-008.html": [
+      "77cceae7a3f044c8d11b1616f9f54469f18d1aca",
+      [
+       null,
+       {}
+      ]
+     ],
+     "revert-val-009.html": [
+      "e9683e90f44a378f16fda177cf2b8cb64d530921",
+      [
+       null,
+       {}
+      ]
+     ],
+     "revert-val-010.html": [
+      "58449e9132b786a2f489a1517b1be3becadaddbf",
+      [
+       null,
+       {}
+      ]
      ]
     },
     "css-color": {
@@ -383279,7 +383411,7 @@
       ]
      ],
      "flexitem-stretch-image.html": [
-      "dd0f8d4f76f1f3dbaf67629315c8e39d73f01df3",
+      "ff3163f6f3d31684db6b22c603f081b6d7c94cfb",
       [
        null,
        {}
@@ -387406,6 +387538,13 @@
        ]
       ]
      },
+     "grid-tracks-stretched-with-different-flex-factors-sum.html": [
+      "f2c1d5e95a2df428432f30fc651b4bf06ae15322",
+      [
+       null,
+       {}
+      ]
+     ],
      "inheritance.html": [
       "eee86f70300d4280531235c813589dc3c399c58c",
       [
@@ -390334,7 +390473,7 @@
       ]
      ],
      "registered-property-revert.html": [
-      "3d0473ea4397fab0440355a11eb0bff941a50323",
+      "33c395d2c2f6f5f9ca868963b8fb3c4d7f593d28",
       [
        null,
        {}
@@ -401358,7 +401497,14 @@
       ]
      ],
      "cssstyledeclaration-csstext.html": [
-      "30d9bd87bde562a827a367241497fdbc34360a9f",
+      "afd54263bfe0ddd6325a82e0c47f663015dbf67c",
+      [
+       null,
+       {}
+      ]
+     ],
+     "cssstyledeclaration-custom-properties.html": [
+      "92cf2c847dceda660ebedd2d8ae798e33b3b1d3b",
       [
        null,
        {}
@@ -438665,7 +438811,7 @@
       },
       "the-label-element": {
        "clicking-interactive-content.html": [
-        "60a80fad9d2aebf284e252949fba7b2bb15af134",
+        "c448df0a38073019112f7f805904a6ec3bd6ef20",
         [
          null,
          {}
@@ -438679,7 +438825,7 @@
         ]
        ],
        "clicking-noninteractive-unlabelable-content.html": [
-        "233168f5664cf972ad579ae4ccba7f674c965d25",
+        "be74ed68330c1f97069e05ed70a2e4908ef6f3c2",
         [
          null,
          {}
@@ -468536,6 +468682,13 @@
       {}
      ]
     ],
+    "subresource-integrity-partial-image.html": [
+     "3abc8399219688f075deec3bf1551188d29f07b9",
+     [
+      null,
+      {}
+     ]
+    ],
     "subresource-integrity.html": [
      "7a35e3bc85eb454f847d1087eaf00cb73b891fb4",
      [
@@ -510489,7 +510642,7 @@
       ]
      ],
      "xrRay_constructor.https.html": [
-      "08f20142e38e9366bd016fb92666b5136128fef6",
+      "d4d727785f1eb5487765249cf6c58dbe1111f3c5",
       [
        null,
        {}
@@ -539889,7 +540042,7 @@
      },
      "add_cookie": {
       "add.py": [
-       "c1a886aafa71757d5efccb3953d2c30a96a14a34",
+       "30804c1dd8ec89f573d3af657de27fe1fe5d9597",
        [
         null,
         {}
@@ -540151,7 +540304,7 @@
      },
      "execute_async_script": {
       "collections.py": [
-       "14848da7e2966939c1efb75eb2b66d389f0b3d38",
+       "484a247cffd9a12acd8024f48fa3db7de59db8d3",
        [
         null,
         {}
@@ -540190,7 +540343,7 @@
      },
      "execute_script": {
       "collections.py": [
-       "f939713c8064d5826e4439acc6b1803ac0a25950",
+       "be0b3a018c505dc26bb2b44969617a9b9daa0793",
        [
         null,
         {}
@@ -540378,7 +540531,7 @@
      },
      "get_alert_text": {
       "get.py": [
-       "d6fdda2d1ed08ecceb5863d78ce915c19d4846fb",
+       "ad0058e0326454147c3b7202daea39864159fd46",
        [
         null,
         {}
@@ -540387,7 +540540,7 @@
      },
      "get_current_url": {
       "get.py": [
-       "39c28c612161e30b114298c7d5eed5ccd60d78d4",
+       "c22e3d410c350248f5eb109e2ab332747e64a453",
        [
         null,
         {}
@@ -540513,7 +540666,7 @@
      },
      "get_named_cookie": {
       "get.py": [
-       "9ea29c8994eb471882ae0ce68aa48b854ba35b99",
+       "1fd5f9f144969419571ab1193e314670925d1fa8",
        [
         null,
         {}
@@ -540742,7 +540895,7 @@
      },
      "new_session": {
       "create_alwaysMatch.py": [
-       "097764e4a999f1def552c5f21fefda3508623385",
+       "a4cc9efc02e2a9c61fb8a79eecd5dcff49ca21a6",
        [
         null,
         {
@@ -540751,7 +540904,7 @@
        ]
       ],
       "create_firstMatch.py": [
-       "f00f6042b085dc09876f67ae650ff62ceb3eb76a",
+       "ec671530f79692c04135ec441426f0044a72e8bc",
        [
         null,
         {
@@ -540769,7 +540922,7 @@
        ]
       ],
       "invalid_capabilities.py": [
-       "f31ce3b8b6fd5f8e4a9ff4d0137debdb7dacdea4",
+       "afdcea0daf706ca32a875db1eb367db0bd2046a7",
        [
         null,
         {}
@@ -540799,7 +540952,7 @@
        ]
       ],
       "response.py": [
-       "16c526ae10bea0540c91a9f7c2291488e4a26119",
+       "dc1328998810faacf74f1b94b54ed59f48e84e4d",
        [
         null,
         {}
@@ -541054,7 +541207,7 @@
      },
      "status": {
       "status.py": [
-       "f0df16a1ee17d22e6293af049876810bb4073929",
+       "1f0f1bc4fe7746f34080cc537701020e4c5b2292",
        [
         null,
         {}
@@ -541063,14 +541216,14 @@
      },
      "switch_to_frame": {
       "cross_origin.py": [
-       "4425a3ab901fef0effb2fc94ca3611e57f2ba51c",
+       "905f1eb56dce07ea82e0de7c5755e2e1b50ed152",
        [
         null,
         {}
        ]
       ],
       "switch.py": [
-       "67b855a96d963ab03efa9495052767ec033b346f",
+       "f9b0e6fc1fcd16c9f9e66b05149930f6ee0ae346",
        [
         null,
         {}
diff --git a/tests/wpt/metadata/css/CSS2/floats/hit-test-floats-002.html.ini b/tests/wpt/metadata/css/CSS2/floats/hit-test-floats-002.html.ini
new file mode 100644
index 00000000000..f64b45fea6b
--- /dev/null
+++ b/tests/wpt/metadata/css/CSS2/floats/hit-test-floats-002.html.ini
@@ -0,0 +1,4 @@
+[hit-test-floats-002.html]
+  [Hit test float]
+    expected: FAIL
+
diff --git a/tests/wpt/metadata/css/css-transforms/transform-scale-hittest.html.ini b/tests/wpt/metadata/css/css-transforms/transform-scale-hittest.html.ini
index 4a1e8110f6f..f8e7e539aae 100644
--- a/tests/wpt/metadata/css/css-transforms/transform-scale-hittest.html.ini
+++ b/tests/wpt/metadata/css/css-transforms/transform-scale-hittest.html.ini
@@ -2,3 +2,6 @@
   [Hit test intersecting scaled box]
     expected: FAIL
 
+  [Hit test within unscaled box]
+    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/elementFromPoint-001.html.ini b/tests/wpt/metadata/css/cssom-view/elementFromPoint-001.html.ini
deleted file mode 100644
index e38782d8c85..00000000000
--- a/tests/wpt/metadata/css/cssom-view/elementFromPoint-001.html.ini
+++ /dev/null
@@ -1,4 +0,0 @@
-[elementFromPoint-001.html]
-  [CSSOM View - 5 - extensions to the Document interface]
-    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 85e94926cb3..5733d536fd3 100644
--- a/tests/wpt/metadata/css/cssom-view/elementFromPosition.html.ini
+++ b/tests/wpt/metadata/css/cssom-view/elementFromPosition.html.ini
@@ -21,3 +21,6 @@
   [test the top of layer]
     expected: FAIL
 
+  [test some point of the element: top left corner]
+    expected: FAIL
+
diff --git a/tests/wpt/metadata/css/cssom-view/elementsFromPoint-invalid-cases.html.ini b/tests/wpt/metadata/css/cssom-view/elementsFromPoint-invalid-cases.html.ini
new file mode 100644
index 00000000000..e181af5397f
--- /dev/null
+++ b/tests/wpt/metadata/css/cssom-view/elementsFromPoint-invalid-cases.html.ini
@@ -0,0 +1,4 @@
+[elementsFromPoint-invalid-cases.html]
+  [The root element is the last element returned for otherwise empty queries within the viewport]
+    expected: FAIL
+
diff --git a/tests/wpt/metadata/css/cssom/cssstyledeclaration-csstext.html.ini b/tests/wpt/metadata/css/cssom/cssstyledeclaration-csstext.html.ini
new file mode 100644
index 00000000000..c6715d49f44
--- /dev/null
+++ b/tests/wpt/metadata/css/cssom/cssstyledeclaration-csstext.html.ini
@@ -0,0 +1,4 @@
+[cssstyledeclaration-csstext.html]
+  [cssText on computed style declaration returns the empty string]
+    expected: FAIL
+
diff --git a/tests/wpt/metadata/css/cssom/cssstyledeclaration-custom-properties.html.ini b/tests/wpt/metadata/css/cssom/cssstyledeclaration-custom-properties.html.ini
new file mode 100644
index 00000000000..595199d7d35
--- /dev/null
+++ b/tests/wpt/metadata/css/cssom/cssstyledeclaration-custom-properties.html.ini
@@ -0,0 +1,4 @@
+[cssstyledeclaration-custom-properties.html]
+  [Custom properties are included in computed style]
+    expected: FAIL
+
diff --git a/tests/wpt/metadata/css/filter-effects/fecomposite-non-zero-inoffset-001.html.ini b/tests/wpt/metadata/css/filter-effects/fecomposite-non-zero-inoffset-001.html.ini
new file mode 100644
index 00000000000..055c56143e6
--- /dev/null
+++ b/tests/wpt/metadata/css/filter-effects/fecomposite-non-zero-inoffset-001.html.ini
@@ -0,0 +1,2 @@
+[fecomposite-non-zero-inoffset-001.html]
+  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 1a8724198c2..2b1fa7f8d7f 100644
--- a/tests/wpt/metadata/fetch/content-type/response.window.js.ini
+++ b/tests/wpt/metadata/fetch/content-type/response.window.js.ini
@@ -312,21 +312,21 @@
   [fetch(): separate response Content-Type: text/plain ]
     expected: NOTRUN
 
-  [<iframe>: separate response Content-Type: text/html;" text/plain]
-    expected: FAIL
-
   [<iframe>: separate response Content-Type: text/html */*;charset=gbk]
     expected: FAIL
 
   [<iframe>: combined response Content-Type: text/html;" \\" text/plain]
     expected: FAIL
 
-  [<iframe>: combined response Content-Type: text/html;charset=gbk text/plain text/html]
-    expected: FAIL
-
-  [<iframe>: separate response Content-Type: text/html */*]
-    expected: FAIL
-
   [<iframe>: combined response Content-Type: text/html;x=" text/plain]
     expected: FAIL
 
+  [<iframe>: combined response Content-Type: text/html;" text/plain]
+    expected: FAIL
+
+  [<iframe>: combined response Content-Type: */* text/html]
+    expected: FAIL
+
+  [<iframe>: separate response Content-Type: 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 d2df9b78483..b2ffc8abf78 100644
--- a/tests/wpt/metadata/fetch/content-type/script.window.js.ini
+++ b/tests/wpt/metadata/fetch/content-type/script.window.js.ini
@@ -56,3 +56,6 @@
   [separate text/javascript x/x]
     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 aa6eb8f6085..30e1b851fd4 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 +11,3 @@
   [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'NosniFF']
-    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_3.html.ini
similarity index 71%
rename from tests/wpt/metadata/html/browsers/history/the-history-interface/traverse_the_history_5.html.ini
rename to tests/wpt/metadata/html/browsers/history/the-history-interface/traverse_the_history_3.html.ini
index dc2e45516de..51f8272a6de 100644
--- 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_3.html.ini
@@ -1,4 +1,4 @@
-[traverse_the_history_5.html]
+[traverse_the_history_3.html]
   [Multiple history traversals, last would be aborted]
     expected: FAIL
 
diff --git a/tests/wpt/metadata/html/interaction/focus/the-autofocus-attribute/supported-elements.html.ini b/tests/wpt/metadata/html/interaction/focus/the-autofocus-attribute/supported-elements.html.ini
index 8b743f36e1d..f1aa94c7ced 100644
--- a/tests/wpt/metadata/html/interaction/focus/the-autofocus-attribute/supported-elements.html.ini
+++ b/tests/wpt/metadata/html/interaction/focus/the-autofocus-attribute/supported-elements.html.ini
@@ -4,7 +4,7 @@
     expected: FAIL
 
   [Element with tabindex should support autofocus]
-    expected: TIMEOUT
+    expected: FAIL
 
   [Host element with delegatesFocus including no focusable descendants should be skipped]
     expected: NOTRUN
@@ -16,5 +16,5 @@
     expected: NOTRUN
 
   [Non-HTMLElement should not support autofocus]
-    expected: NOTRUN
+    expected: TIMEOUT
 
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..dc856a3d5a3 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 +1,5 @@
 [iframe_sandbox_popups_nonescaping-3.html]
   type: testharness
-  expected: TIMEOUT
   [Check that popups from a sandboxed iframe do not escape the sandbox]
-    expected: NOTRUN
+    expected: FAIL
 
diff --git a/tests/wpt/metadata/html/webappapis/scripting/processing-model-2/integration-with-the-javascript-job-queue/promise-job-entry.html.ini b/tests/wpt/metadata/html/webappapis/scripting/processing-model-2/integration-with-the-javascript-job-queue/promise-job-entry.html.ini
index d16e3ccb769..a1effd5f801 100644
--- a/tests/wpt/metadata/html/webappapis/scripting/processing-model-2/integration-with-the-javascript-job-queue/promise-job-entry.html.ini
+++ b/tests/wpt/metadata/html/webappapis/scripting/processing-model-2/integration-with-the-javascript-job-queue/promise-job-entry.html.ini
@@ -1,5 +1,4 @@
 [promise-job-entry.html]
-  expected: TIMEOUT
   [Fulfillment handler on fulfilled promise]
     expected: FAIL
 
@@ -16,5 +15,5 @@
     expected: FAIL
 
   [Fulfillment handler on pending-then-fulfilled promise]
-    expected: TIMEOUT
+    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 8b1c7d6c5f5..64ff19b7967 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
@@ -143,3 +143,6 @@
   [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 44065 more errors.\n\tMax AbsError of 1.9986611604690552e+0 at index of 15080.\n\t[15080\]\t-9.9994289875030518e-1\t9.9871826171875000e-1\t1.9986611604690552e+0\t2.0012262087101997e+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 44059 more errors.\n\tMax AbsError of 1.9986611604690552e+0 at index of 17285.\n\t[17285\]\t-9.9994289875030518e-1\t9.9871826171875000e-1\t1.9986611604690552e+0\t2.0012262087101997e+0\t3.0517578125000000e-5\n\tMax RelError of Infinity at index of 12348.\n\t[12348\]\t9.5105654001235962e-1\t0.0000000000000000e+0\t9.5105654001235962e-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 ecdef72749c..65919c2c6d2 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
@@ -353,3 +353,9 @@
   [X Stitched sine-wave buffers at sample rate 44100 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":0.000090957,"relativeThreshold":0}.\n\tIndex\tActual\t\t\tExpected\t\tAbsError\t\tRelError\t\tTest threshold\n\t[31080\]\t-6.7816996732928000e+14\t5.6332010030746460e-1\t6.7816996732928063e+14\t1.2038802928550393e+15\t9.0957000000000003e-5\n\t[31081\]\t4.5854689648100989e-41\t6.1397600173950195e-1\t6.1397600173950195e-1\t1.0000000000000000e+0\t9.0957000000000003e-5\n\tMax AbsError of 6.7816996732928063e+14 at index of 31080.\n\tMax RelError of 1.2038802928550393e+15 at index of 31080.\n]
     expected: FAIL
 
+  [X SNR (45.01863889941501 dB) is not greater than or equal to 85.58. Got 45.01863889941501.]
+    expected: FAIL
+
+  [X Stitched sine-wave buffers at sample rate 44100 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":0.000090957,"relativeThreshold":0}.\n\tIndex\tActual\t\t\tExpected\t\tAbsError\t\tRelError\t\tTest threshold\n\t[31080\]\t5.6092996914003379e-10\t5.6332010030746460e-1\t5.6332009974653463e-1\t9.9999999900424297e-1\t9.0957000000000003e-5\n\t[31081\]\t4.5875709125065861e-41\t6.1397600173950195e-1\t6.1397600173950195e-1\t1.0000000000000000e+0\t9.0957000000000003e-5\n\tMax AbsError of 6.1397600173950195e-1 at index of 31081.\n\tMax RelError of 1.0000000000000000e+0 at index of 31081.\n]
+    expected: FAIL
+
diff --git a/tests/wpt/web-platform-tests/contenteditable/META.yml b/tests/wpt/web-platform-tests/contenteditable/META.yml
new file mode 100644
index 00000000000..3618b8d29d0
--- /dev/null
+++ b/tests/wpt/web-platform-tests/contenteditable/META.yml
@@ -0,0 +1,3 @@
+spec: https://w3c.github.io/contentEditable/
+suggested_reviewers:
+  - marcoscaceres
diff --git a/tests/wpt/web-platform-tests/contenteditable/plaintext-only.html b/tests/wpt/web-platform-tests/contenteditable/plaintext-only.html
new file mode 100644
index 00000000000..cb8308edcc4
--- /dev/null
+++ b/tests/wpt/web-platform-tests/contenteditable/plaintext-only.html
@@ -0,0 +1,20 @@
+<!DOCTYPE html>
+<meta charset="utf-8">
+<title>contenteditable="plaintext-only" should exist</title>
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<div id="txt" contenteditable="plaintext-only"></div>
+<script>
+test(function() {
+    const txt = document.getElementById('txt');
+    assert_true(txt.isContentEditable);
+    assert_equals(txt.contentEditable, 'plaintext-only');
+}, 'plaintext-only is an accepted attribute value for contenteditable');
+test(function() {
+    const txt = document.createElement('div');
+    assert_false(txt.isContentEditable);
+    txt.contentEditable = 'plaintext-only';
+    assert_true(txt.isContentEditable);
+    assert_equals(txt.contentEditable, 'plaintext-only');
+}, 'plaintext-only can be assigned to contenteditable dynamically');
+</script>
diff --git a/tests/wpt/web-platform-tests/css/css-cascade/revert-val-006.html b/tests/wpt/web-platform-tests/css/css-cascade/revert-val-006.html
new file mode 100644
index 00000000000..2b238f6d7e5
--- /dev/null
+++ b/tests/wpt/web-platform-tests/css/css-cascade/revert-val-006.html
@@ -0,0 +1,28 @@
+<!DOCTYPE html>
+<title>CSS Cascade: 'revert' keyword in keyframe animations</title>
+<link rel="help" href="https://drafts.csswg.org/css-cascade/#default">
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<style>
+  @keyframes test {
+    from { margin-top: 0px; }
+    50% { margin-top: revert; }
+    to { margin-top: 0px; }
+  }
+  #h1 {
+    margin-top: 0px;
+    animation: test linear 1000s -500s;
+  }
+</style>
+<h1 id=h1></h1>
+<h1 id=ref></h1>
+<script>
+  test(function() {
+    let actual = getComputedStyle(h1).marginTop;
+    let expected = getComputedStyle(ref).marginTop;
+    // This test assumes that the UA style sheet sets a non-0px value on
+    // <h1> elements:
+    assert_not_equals(expected, '0px');
+    assert_equals(actual, expected);
+  }, 'The revert keyword works with @keyframes');
+</script>
diff --git a/tests/wpt/web-platform-tests/css/css-cascade/revert-val-007.html b/tests/wpt/web-platform-tests/css/css-cascade/revert-val-007.html
new file mode 100644
index 00000000000..38078fcfa9a
--- /dev/null
+++ b/tests/wpt/web-platform-tests/css/css-cascade/revert-val-007.html
@@ -0,0 +1,34 @@
+<!DOCTYPE html>
+<title>CSS Cascade: 'revert' in keyframe animations on identical elements</title>
+<link rel="help" href="https://drafts.csswg.org/css-cascade/#default">
+<link rel="help" href="https://crbug.com/1065387">
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<style>
+  @keyframes test {
+    from { margin-top: revert; }
+    to { margin-top: 100px; }
+  }
+  .anim {
+    margin-top: 0px;
+    animation: test linear 1s paused;
+  }
+</style>
+<h1 class="anim"></h1>
+<h1 class="anim"></h1>
+<h1 class="anim"></h1>
+<h1 id=ref></h1>
+<script>
+  test(function() {
+    // This querySelectorAll includes #ref, but that's OK.
+    let targets = document.querySelectorAll('h1');
+    for (let t of targets) {
+      let actual = getComputedStyle(t).marginTop;
+      let expected = getComputedStyle(ref).marginTop;
+      // This test assumes that the UA style sheet sets a non-0px value on
+      // <h1> elements:
+      assert_not_equals(expected, '0px');
+      assert_equals(actual, expected);
+    }
+  }, 'A @keyframe animation with revert works when applied to multiple identical elements');
+</script>
diff --git a/tests/wpt/web-platform-tests/css/css-cascade/revert-val-008.html b/tests/wpt/web-platform-tests/css/css-cascade/revert-val-008.html
new file mode 100644
index 00000000000..77cceae7a3f
--- /dev/null
+++ b/tests/wpt/web-platform-tests/css/css-cascade/revert-val-008.html
@@ -0,0 +1,32 @@
+<!DOCTYPE html>
+<title>CSS Cascade: 'revert' in final keyframe of web animation</title>
+<link rel="help" href="https://drafts.csswg.org/css-cascade/#default">
+<link rel="help" href="https://crbug.com/1065387">
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<h1 id=h1></h1>
+<h1 id=ref></h1>
+<script>
+  test(function() {
+    let expected_lower = parseInt(getComputedStyle(ref).marginTop);
+    let expected_upper = expected_lower * 2;
+
+    h1.animate([
+      { marginTop: `${expected_lower * 4}px` },
+      { marginTop: `${expected_lower * 3}px` },
+      { marginTop: `${expected_lower * 2}px` },
+      { marginTop: 'revert' },
+    ], {
+      duration: 4000,
+      delay: -3500,
+    }).pause();
+
+    let actual = parseInt(getComputedStyle(h1).marginTop);
+
+    // This test assumes that the UA style sheet sets a non-0px value on
+    // <h1> elements:
+    assert_not_equals(expected_lower, 0);
+    assert_not_equals(expected_upper, 0);
+    assert_between_exclusive(actual, expected_lower, expected_upper);
+  }, 'The revert keyword works in the final frame of a web animation');
+</script>
diff --git a/tests/wpt/web-platform-tests/css/css-cascade/revert-val-009.html b/tests/wpt/web-platform-tests/css/css-cascade/revert-val-009.html
new file mode 100644
index 00000000000..e9683e90f44
--- /dev/null
+++ b/tests/wpt/web-platform-tests/css/css-cascade/revert-val-009.html
@@ -0,0 +1,30 @@
+<!DOCTYPE html>
+<title>CSS Cascade: 'revert' in implicit keyframes</title>
+<link rel="help" href="https://drafts.csswg.org/css-cascade/#default">
+<link rel="help" href="https://crbug.com/1065387">
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<h1 id=h1></h1>
+<h1 id=ref></h1>
+<script>
+  test(function() {
+    let expected_lower = parseInt(getComputedStyle(ref).marginTop);
+    let expected_upper = expected_lower * 2;
+    h1.style = `margin-top: ${expected_lower * 1000}px; margin-top: revert;`;
+
+    h1.animate([
+      { marginTop: `${expected_upper}px` },
+    ], {
+      duration: 1000,
+      delay: -500,
+    }).pause();
+
+    let actual = parseInt(getComputedStyle(h1).marginTop);
+
+    // This test assumes that the UA style sheet sets a non-0px value on
+    // <h1> elements:
+    assert_not_equals(expected_lower, 0);
+    assert_not_equals(expected_upper, 0);
+    assert_between_exclusive(actual, expected_lower, expected_upper);
+  }, 'The revert keyword works in implicit keyframes');
+</script>
diff --git a/tests/wpt/web-platform-tests/css/css-cascade/revert-val-010.html b/tests/wpt/web-platform-tests/css/css-cascade/revert-val-010.html
new file mode 100644
index 00000000000..58449e9132b
--- /dev/null
+++ b/tests/wpt/web-platform-tests/css/css-cascade/revert-val-010.html
@@ -0,0 +1,36 @@
+<!DOCTYPE html>
+<title>CSS Cascade: 'revert' appearing in setKeyframes</title>
+<link rel="help" href="https://drafts.csswg.org/css-cascade/#default">
+<link rel="help" href="https://drafts.csswg.org/web-animations-1/#dom-keyframeeffect-setkeyframes">
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<h1 id=h1></h1>
+<script>
+  test(function() {
+    let original = parseInt(getComputedStyle(h1).marginTop);
+
+    // This test assumes that the UA style sheet sets a non-0px value on
+    // <h1> elements:
+    assert_not_equals(original, 0);
+
+    let animation = h1.animate([
+      { marginTop: `${original*4}px` },
+      { marginTop: `${original*8}px` },
+    ], {
+      duration: 1000000,
+      delay: -500000,
+      easing: 'steps(2, end)'
+    });
+
+    let animated = parseInt(getComputedStyle(h1).marginTop);
+    assert_equals(animated, original*6);
+
+    animation.effect.setKeyframes([
+      { marginTop: 'revert' },
+      { marginTop: `${original*3}px` },
+    ]);
+
+    let animated_revert = parseInt(getComputedStyle(h1).marginTop);
+    assert_equals(animated_revert, original*2);
+  }, 'The revert works when appearing in setKeyframes');
+</script>
diff --git a/tests/wpt/web-platform-tests/css/css-flexbox/flexitem-stretch-image.html b/tests/wpt/web-platform-tests/css/css-flexbox/flexitem-stretch-image.html
index dd0f8d4f76f..ff3163f6f3d 100644
--- a/tests/wpt/web-platform-tests/css/css-flexbox/flexitem-stretch-image.html
+++ b/tests/wpt/web-platform-tests/css/css-flexbox/flexitem-stretch-image.html
@@ -28,8 +28,8 @@ to fit the size of flexitem according to flex values.">
 <div id=log></div>
 
 <div class="flexbox">
-  <img data-expected-display="block" data-expected-width="345" style="flex: 1 0 auto;" src="support/100x100-blue.png">
-  <img data-expected-display="block" data-expected-width="255" data-expected-height="100" style="flex: 1 0 auto;" src="support/10x10-green.png">
+  <img data-expected-display="block" data-expected-width="345" data-expected-height="345" style="flex: 1 0 auto;" src="support/100x100-blue.png">
+  <img data-expected-display="block" data-expected-width="255" data-expected-height="345" style="flex: 1 0 auto;" src="support/10x10-green.png">
 </div>
 
 </body>
diff --git a/tests/wpt/web-platform-tests/css/css-flexbox/negative-flex-margins-crash.html b/tests/wpt/web-platform-tests/css/css-flexbox/negative-flex-margins-crash.html
new file mode 100644
index 00000000000..8bcc566c0f7
--- /dev/null
+++ b/tests/wpt/web-platform-tests/css/css-flexbox/negative-flex-margins-crash.html
@@ -0,0 +1,21 @@
+<!DOCTYPE html>
+<title>CSS Flexbox: Crash caused by negative width in flex box</title>
+<link rel="author" title="Christian Biesinger" href="mailto:cbiesinger@chromium.org">
+<link rel="help" href="https://drafts.csswg.org/css-flexbox-1/#box-model">
+<link rel="issue" href="https://crbug.com/490423">
+<meta name="assert" content="Check that crash doesn't happen in flex box with negative margin.">
+
+<style>
+div {
+  display: flex;
+}
+
+.inner {
+  margin-left: -4em;
+}
+</style>
+<div>
+    <div>
+        <div class="inner">PASS if we don't assert</div>
+    </div>
+</div>
diff --git a/tests/wpt/web-platform-tests/css/css-flexbox/negative-flex-rounding-crash.html b/tests/wpt/web-platform-tests/css/css-flexbox/negative-flex-rounding-crash.html
new file mode 100644
index 00000000000..ad69cc059ec
--- /dev/null
+++ b/tests/wpt/web-platform-tests/css/css-flexbox/negative-flex-rounding-crash.html
@@ -0,0 +1,46 @@
+<!DOCTYPE html>
+<title>CSS Flexbox: Crash caused by rounding error in flex-shrink</title>
+<link rel="author" title="Tony Chang" href="mailto:tony@chromium.org">
+<link rel="help" href="https://drafts.csswg.org/css-flexbox/#resolve-flexible-lengths">
+<link rel="issue" href="https://bugs.webkit.org/show_bug.cgi?id=97606">
+<meta name="assert" content="Check that crash doesn't happen in flex-shrink due to floating point precision errors.">
+
+<style>
+.math {
+    display: inline-flex;
+}
+.math > * {
+    padding-bottom: 0.35em;
+}
+.mfrac {
+    display: inline-flex;
+    flex-direction: column;
+}
+.mfrac > :first-child {
+    margin-block-end: 0.2em;
+}
+.mfrac > :last-child {
+    margin-block-start: 0.2em;
+}
+.x {
+    line-height: 9px;
+}
+.y {
+    line-height: 12px;
+}
+</style>
+<div class=math>
+    <div class=mfrac>
+        <div class=mfrac>
+            <div class=x>x</div>
+            <div class=y>y</div>
+        </div>
+        <div class=mfrac>
+            <div class=mfrac>
+                <div class=x>x</div>
+                <div class=y>y</div>
+            </div>
+            <div class=x>z</div>
+        </div>
+    </div>
+</div>
diff --git a/tests/wpt/web-platform-tests/css/css-grid/grid-model/grid-layout-stale-001.html b/tests/wpt/web-platform-tests/css/css-grid/grid-model/grid-layout-stale-001.html
new file mode 100644
index 00000000000..bb81546678c
--- /dev/null
+++ b/tests/wpt/web-platform-tests/css/css-grid/grid-model/grid-layout-stale-001.html
@@ -0,0 +1,42 @@
+<!doctype html>
+<title>CSS Grid: Do not add non-children of the grid into the grid container</title>
+<link rel="author" title="Sergio Villar" href="mailto:svillar@igalia.com">
+<link rel="help" href="https://drafts.csswg.org/css-grid">
+<link rel="help" href="https://crbug.com/313293">
+<link rel="match" href="reference/grid-layout-stale-001-ref.html">
+<meta name="assert" content="Check that we do not add non-children of the grid into the grid representation."/>
+
+<script src="/resources/testdriver.js"></script>
+<script src="/resources/testdriver-actions.js"></script>
+<script src="/resources/testdriver-vendor.js"></script>
+
+<style>
+  embed { position: absolute; }
+  .c1 { animation-delay: 45762s; }
+</style>
+
+<p>This test passes if it doesn't crash and it matches the reference.</p>
+<div style="display: grid;">
+    <embed type="something-not-js">
+</div>
+
+<script>
+function keyPress(key) {
+  let actions = new test_driver.Actions()
+    .keyDown(key)
+    .keyUp(key);
+
+  return actions.send();
+}
+function crash() {
+  var highlight = document.createElementNS("http://www.w3.org/1999/xhtml", "highlight");
+  highlight.setAttribute("class", "c1");
+  document.body.appendChild(highlight);
+
+  for (i=0; i != 8; i++)
+    keyPress("\t");
+  keyPress("X");
+}
+
+document.addEventListener("DOMContentLoaded", crash, false);
+</script>
\ No newline at end of file
diff --git a/tests/wpt/web-platform-tests/css/css-grid/grid-model/grid-layout-stale-002.html b/tests/wpt/web-platform-tests/css/css-grid/grid-model/grid-layout-stale-002.html
new file mode 100644
index 00000000000..ea11cd5c5cb
--- /dev/null
+++ b/tests/wpt/web-platform-tests/css/css-grid/grid-model/grid-layout-stale-002.html
@@ -0,0 +1,30 @@
+<!DOCTYPE html>
+<title>CSS Grid: Do not leave stale pointers into the grid container</title>
+<link rel="author" title="Sergio Villar" href="mailto:svillar@igalia.com">
+<link rel="help" href="https://drafts.csswg.org/css-grid">
+<link rel="help" href="https://crbug.com/313293">
+<link rel="match" href="reference/grid-layout-stale-002-ref.html">
+<meta name="assert" content="Check that we don't leave stale pointers into the internal grid representation."/>
+
+<script src="/resources/testdriver.js"></script>
+<script src="/resources/testdriver-actions.js"></script>
+<script src="/resources/testdriver-vendor.js"></script>
+
+<p>This test passes if it doesn't crash and it matches the reference.</p>
+<span style="display: grid" contenteditable=plaintext-only></span>
+<script>
+function keyPress(key) {
+  let actions = new test_driver.Actions()
+    .keyDown(key)
+    .keyUp(key);
+
+  return actions.send();
+}
+function crash() {
+    keyPress("\t");
+    keyPress("X");
+    document.designMode = 'on';
+    document.execCommand("InsertHTML", false, "<div>");
+}
+document.addEventListener("DOMContentLoaded", crash, false);
+</script>
diff --git a/tests/wpt/web-platform-tests/css/css-grid/grid-model/reference/grid-layout-stale-001-ref.html b/tests/wpt/web-platform-tests/css/css-grid/grid-model/reference/grid-layout-stale-001-ref.html
new file mode 100644
index 00000000000..3ade075c99c
--- /dev/null
+++ b/tests/wpt/web-platform-tests/css/css-grid/grid-model/reference/grid-layout-stale-001-ref.html
@@ -0,0 +1,13 @@
+<!doctype html>
+<title>CSS Grid: Do not add non-children of the grid into the grid container</title>
+
+<style>
+  embed { position: absolute; }
+  .c1 { animation-delay: 45762s; }
+</style>
+
+<p>This test passes if it doesn't crash and it matches the reference.</p>
+<div style="display: grid;">
+  <embed type="something-not-js">
+</div>
+<highlight class="c1"></highlight>
diff --git a/tests/wpt/web-platform-tests/css/css-grid/grid-model/reference/grid-layout-stale-002-ref.html b/tests/wpt/web-platform-tests/css/css-grid/grid-model/reference/grid-layout-stale-002-ref.html
new file mode 100644
index 00000000000..5d4d996106d
--- /dev/null
+++ b/tests/wpt/web-platform-tests/css/css-grid/grid-model/reference/grid-layout-stale-002-ref.html
@@ -0,0 +1,4 @@
+<!DOCTYPE html>
+<title>CSS Grid: Do not leave stale pointers into the grid container</title>
+<p>This test passes if it doesn't crash and it matches the reference.</p>
+<span style="display: grid" contenteditable=plaintext-only></span>
diff --git a/tests/wpt/web-platform-tests/css/css-grid/grid-tracks-stretched-with-different-flex-factors-sum.html b/tests/wpt/web-platform-tests/css/css-grid/grid-tracks-stretched-with-different-flex-factors-sum.html
new file mode 100644
index 00000000000..f2c1d5e95a2
--- /dev/null
+++ b/tests/wpt/web-platform-tests/css/css-grid/grid-tracks-stretched-with-different-flex-factors-sum.html
@@ -0,0 +1,57 @@
+<!DOCTYPE html>
+<title>CSS Grid: 'stretch' content alignment on flex tracks.</title>
+<link rel="author" title="Javier Fernandez" href="mailto:jfernandez@igalia.com">
+<link rel="help" href="https://drafts.csswg.org/css-align-3/#content-distribution">
+<link rel="help" href="https://drafts.csswg.org/css-align-3/#valdef-align-content-stretch">
+<meta name="assert" content="This test ensures that using flex tracks and 'stretch' value for the content alignment css properties work properly."/>
+<link href="/css/support/grid.css" rel="stylesheet"/>
+<link href="/css/support/alignment.css" rel="stylesheet"/>
+
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<script src="/resources/check-layout-th.js"></script>
+<style>
+body {
+  margin: 0;
+}
+
+.grid {
+  position: relative;
+  width: 200px;
+  height: 300px;
+}
+
+.fractionFlexTracks {
+  grid-template-columns: auto 0.25fr;
+  grid-template-rows: 0.2fr auto;
+}
+
+.flexTracks {
+  grid-template-columns: auto 1fr;
+  grid-template-rows: 1.5fr auto;
+}
+
+</style>
+</head>
+<body onload="checkLayout('.grid')">
+
+<div style="position: relative">
+  <p>When the sum of all track's flex factor is < 1, they don't exhaust the available space, which is used to stretch the 'auto' sized tracks.</p>
+  <div class="grid fractionFlexTracks contentStretch" data-expected-width="200" data-expected-height="300">
+    <div class="firstRowFirstColumn" data-offset-x="0" data-offset-y="0" data-expected-width="150" data-expected-height="60"></div>
+    <div class="firstRowSecondColumn" data-offset-x="150" data-offset-y="0" data-expected-width="50" data-expected-height="60"></div>
+    <div class="secondRowFirstColumn" data-offset-x="0" data-offset-y="60" data-expected-width="150" data-expected-height="240"></div>
+    <div class="secondRowSecondColumn" data-offset-x="150" data-offset-y="60" data-expected-width="50" data-expected-height="240"></div>
+  </div>
+</div>
+
+<div style="position: relative">
+  <p>When the sum of all track's flex factor is >= 1, they exhaust the available space, hence the 'stretch' alignment is not applied to the 'auto' sized tracks.</p>
+  <div class="grid flexTracks contentStretch" data-expected-width="200" data-expected-height="300">
+    <div class="firstRowFirstColumn" data-offset-x="0" data-offset-y="0" data-expected-width="0" data-expected-height="300"></div>
+    <div class="firstRowSecondColumn" data-offset-x="0" data-offset-y="0" data-expected-width="200" data-expected-height="300"></div>
+    <div class="secondRowFirstColumn" data-offset-x="0" data-offset-y="300" data-expected-width="0" data-expected-height="0"></div>
+    <div class="secondRowSecondColumn" data-offset-x="0" data-offset-y="300" data-expected-width="200" data-expected-height="0"></div>
+  </div>
+</div>
+</body>
diff --git a/tests/wpt/web-platform-tests/css/css-properties-values-api/registered-property-revert.html b/tests/wpt/web-platform-tests/css/css-properties-values-api/registered-property-revert.html
index 3d0473ea439..33c395d2c2f 100644
--- a/tests/wpt/web-platform-tests/css/css-properties-values-api/registered-property-revert.html
+++ b/tests/wpt/web-platform-tests/css/css-properties-values-api/registered-property-revert.html
@@ -14,11 +14,33 @@
         --inherited: revert;
         --non-inherited: revert;
     }
+
+    @keyframes revert_animation {
+        from {
+            --animated-inherited: revert;
+            --animated-non-inherited: revert;
+        }
+        to {
+            --animated-inherited: 100px;
+            --animated-non-inherited: 100px;
+        }
+    }
+
+    #animated_parent {
+        --animated-inherited: 0px;
+    }
+    #animated_child {
+        animation: revert_animation 10s -5s linear paused;
+    }
 </style>
 <div id=parent>
     <div id=child>
     </div>
 </div>
+<div id=animated_parent>
+    <div id=animated_child>
+    </div>
+</div>
 <script>
 
 CSS.registerProperty({
@@ -35,6 +57,20 @@ CSS.registerProperty({
     inherits: false
 });
 
+CSS.registerProperty({
+    name: "--animated-non-inherited",
+    syntax: "<length>",
+    initialValue: "0px",
+    inherits: false
+});
+
+CSS.registerProperty({
+    name: "--animated-inherited",
+    syntax: "<length>",
+    initialValue: "10000px",
+    inherits: true
+});
+
 test(function(){
     let cs = getComputedStyle(child);
     assert_equals(cs.getPropertyValue('--inherited'), '10px');
@@ -45,4 +81,14 @@ test(function(){
     assert_equals(cs.getPropertyValue('--non-inherited'), '0px');
 }, 'Non-inherited registered custom property can be reverted');
 
+test(function(){
+    let cs = getComputedStyle(animated_child);
+    assert_equals(cs.getPropertyValue('--animated-non-inherited'), '50px');
+}, 'Non-inherited registered custom property can be reverted in animation');
+
+test(function(){
+    let cs = getComputedStyle(animated_child);
+    assert_equals(cs.getPropertyValue('--animated-inherited'), '50px');
+}, 'Inherited registered custom property can be reverted in animation');
+
 </script>
diff --git a/tests/wpt/web-platform-tests/css/cssom/cssstyledeclaration-csstext.html b/tests/wpt/web-platform-tests/css/cssom/cssstyledeclaration-csstext.html
index 30d9bd87bde..afd54263bfe 100644
--- a/tests/wpt/web-platform-tests/css/cssom/cssstyledeclaration-csstext.html
+++ b/tests/wpt/web-platform-tests/css/cssom/cssstyledeclaration-csstext.html
@@ -97,6 +97,18 @@
 
         }, 'invalid property does not appear');
 
+        // https://github.com/w3c/csswg-drafts/issues/1033
+        test(function() {
+            var elm = newElm();
+            var style = elm.style;
+
+            style.color = 'red';
+            style.unknown = 'unknown';
+            style.fontSize = '10pt';
+
+            assert_not_equals(getComputedStyle(elm).length, 0, "Should have a style");
+            assert_equals(getComputedStyle(elm).cssText, "", "cssText is empty");
+        }, 'cssText on computed style declaration returns the empty string');
     </script>
     </body>
 </html>
diff --git a/tests/wpt/web-platform-tests/css/cssom/cssstyledeclaration-custom-properties.html b/tests/wpt/web-platform-tests/css/cssom/cssstyledeclaration-custom-properties.html
new file mode 100644
index 00000000000..92cf2c847dc
--- /dev/null
+++ b/tests/wpt/web-platform-tests/css/cssom/cssstyledeclaration-custom-properties.html
@@ -0,0 +1,19 @@
+<!doctype html>
+<title>CSS Test: computed style declaration includes custom properties.</title>
+<link rel="author" href="mailto:emilio@crisal.io" title="Emilio Cobos Álvarez">
+<link rel="author" href="https://mozilla.org" title="Mozilla">
+<link rel="help" href="https://drafts.csswg.org/cssom/#dom-window-getcomputedstyle">
+<link rel="help" href="https://github.com/w3c/csswg-drafts/issues/1316">
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<div style="--foo:bar"></div>
+<div></div>
+<script>
+  test(function() {
+    let withCustom = getComputedStyle(document.querySelector("div"));
+    let withoutCustom = getComputedStyle(document.querySelector("div + div"));
+    assert_equals(withCustom.getPropertyValue("--foo"), "bar", "Should be returned from getPropertyValue");
+    assert_equals(withCustom.length, withoutCustom.length + 1, "Should show up in .length");
+    assert_equals(withCustom[withCustom.length - 1], "--foo", "Should be after all the non-custom properties");
+  }, "Custom properties are included in computed style");
+</script>
diff --git a/tests/wpt/web-platform-tests/css/filter-effects/fecomposite-non-zero-inoffset-001.html b/tests/wpt/web-platform-tests/css/filter-effects/fecomposite-non-zero-inoffset-001.html
new file mode 100644
index 00000000000..b2d71cfa981
--- /dev/null
+++ b/tests/wpt/web-platform-tests/css/filter-effects/fecomposite-non-zero-inoffset-001.html
@@ -0,0 +1,21 @@
+<!DOCTYPE html>
+<title>CSS Filters: Correct destination rectangle in feComposite</title>
+<link rel="help" href="https://drafts.fxtf.org/filter-effects/#FilterProperty">
+<link rel="help" href="https://drafts.fxtf.org/filter-effects/#feMorphologyElement">
+<link rel="help" href="https://drafts.fxtf.org/filter-effects/#feFloodElement">
+<link rel="help" href="https://drafts.fxtf.org/filter-effects/#feCompositeElement">
+<link rel="issue" href="https://bugs.chromium.org/p/chromium/issues/detail?id=391200">
+<link rel="match" href="reference/fecomposite-non-zero-inoffset-001-ref.html">
+<meta name="assert" content="This test ensures that feComposite with 'operator=in' works properly on the correct destination rectangle.">
+<body>
+  <div style="filter: url('#filter'); width: 100px; height: 100px; padding: 1px;">
+    <div style="background-color: red; width: 98px; height: 98px;"></div>
+  </div>
+  <svg width="0" height="0">
+    <filter id="filter">
+      <feFlood result="outlineColor" flood-color="green"/>
+      <feMorphology in="SourceAlpha" operator="dilate" radius="1"/>
+      <feComposite operator="in" in="outlineColor"/>
+    </filter>
+  </svg>
+</body>
diff --git a/tests/wpt/web-platform-tests/css/filter-effects/reference/fecomposite-non-zero-inoffset-001-ref.html b/tests/wpt/web-platform-tests/css/filter-effects/reference/fecomposite-non-zero-inoffset-001-ref.html
new file mode 100644
index 00000000000..e4900ad0476
--- /dev/null
+++ b/tests/wpt/web-platform-tests/css/filter-effects/reference/fecomposite-non-zero-inoffset-001-ref.html
@@ -0,0 +1,4 @@
+<!DOCTYPE html>
+<body>
+  <div style="width: 100px; height: 100px; background-color: green;"></div>
+</body>
diff --git a/tests/wpt/web-platform-tests/css/filter-effects/reference/remove-filter-repaint-ref.html b/tests/wpt/web-platform-tests/css/filter-effects/reference/remove-filter-repaint-ref.html
new file mode 100644
index 00000000000..bde2a93360b
--- /dev/null
+++ b/tests/wpt/web-platform-tests/css/filter-effects/reference/remove-filter-repaint-ref.html
@@ -0,0 +1,41 @@
+<!DOCTYPE html>
+<html>
+<head>
+    <title>CSS Filters: Repaint a compositing layer</title>
+    <style>
+    .backdrop {
+        position: absolute;
+        top: 0;
+        left: 0;
+        height: 100px;
+        width: 100px;
+        background-color: silver;
+    }
+
+    .overlay {
+        position: absolute;
+        top: 50px;
+        left: 50px;
+        width: 400px;
+        height: 100px;
+        background: gray;
+        box-shadow: 0 0 4px black;
+    }
+
+    .play {
+        font-size: 36pt;
+        background-color: navy;
+        color: white;
+    }
+    .composited {
+        will-change: transform;
+    }
+    </style>
+</head>
+<body>
+    <div class="composited backdrop"></div>
+    <div class="overlay">
+        <span id="play" class="play changed">this should be visible</span>
+    </div>
+</body>
+</html>
diff --git a/tests/wpt/web-platform-tests/css/filter-effects/remove-filter-repaint.html b/tests/wpt/web-platform-tests/css/filter-effects/remove-filter-repaint.html
new file mode 100644
index 00000000000..a9af9db34ee
--- /dev/null
+++ b/tests/wpt/web-platform-tests/css/filter-effects/remove-filter-repaint.html
@@ -0,0 +1,60 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <title>CSS Filters: Repaint a compositing layer</title>
+  <link rel="author" title="Simon Fraser" href="mailto:simon.fraser@apple.com>">
+  <link rel="help" href="https://drafts.fxtf.org/filter-effects/#dropshadowEquivalent">
+  <link rel="issue" href="https://bugs.webkit.org/show_bug.cgi?id=120135">
+  <link rel="issue" href="https://chromiumcodereview.appspot.com/23526037">
+  <link rel="match" href="reference/remove-filter-repaint-ref.html">
+  <meta name="assert" content="This test ensures that we can repaint the compositing layer when removing a filter on an inline child of a compositing layer.">
+  <script src="/common/reftest-wait.js"></script>
+  <style>
+    .backdrop {
+      position: absolute;
+      top: 0;
+      left: 0;
+      height: 100px;
+      width: 100px;
+      background-color: silver;
+    }
+    .overlay {
+      position: absolute;
+      top: 50px;
+      left: 50px;
+      width: 400px;
+      height: 100px;
+      background: gray;
+      box-shadow: 0 0 4px black;
+    }
+    .play {
+      font-size: 36pt;
+      background-color: navy;
+      color: white;
+    }
+    .play.changed {
+      filter: drop-shadow(black 0 0 5px);
+    }
+    .composited {
+      will-change: transform;
+    }
+    </style>
+    <script>
+      function doTest() {
+        requestAnimationFrame(function() {
+          requestAnimationFrame(function() {
+            document.getElementById('play').classList.remove('changed');
+            takeScreenshot();
+          });
+        });
+      }
+      window.addEventListener('load', doTest, false);
+  </script>
+</head>
+<body>
+  <div class="composited backdrop"></div>
+  <div class="overlay">
+    <span id="play" class="play changed">this should be visible</span>
+  </div>
+</body>
+</html>
diff --git a/tests/wpt/web-platform-tests/html/semantics/forms/the-label-element/clicking-interactive-content.html b/tests/wpt/web-platform-tests/html/semantics/forms/the-label-element/clicking-interactive-content.html
index 60a80fad9d2..c448df0a380 100644
--- a/tests/wpt/web-platform-tests/html/semantics/forms/the-label-element/clicking-interactive-content.html
+++ b/tests/wpt/web-platform-tests/html/semantics/forms/the-label-element/clicking-interactive-content.html
@@ -19,17 +19,6 @@
   <select></select>
   <textarea></textarea>
   <video controls></video>
-
-  <div tabindex=""></div>
-
-  <!-- These are interesting in that even without tabindex, they could become
-  interactive with the addition/removal of an attribute. -->
-  <a tabindex=""></a>
-  <audio tabindex=""></audio>
-  <img tabindex="">
-  <input type=hidden tabindex="">
-  <object tabindex=""></object>
-  <video tabindex=""></video>
 </template>
 
 <script>
diff --git a/tests/wpt/web-platform-tests/html/semantics/forms/the-label-element/clicking-noninteractive-unlabelable-content.html b/tests/wpt/web-platform-tests/html/semantics/forms/the-label-element/clicking-noninteractive-unlabelable-content.html
index 233168f5664..be74ed68330 100644
--- a/tests/wpt/web-platform-tests/html/semantics/forms/the-label-element/clicking-noninteractive-unlabelable-content.html
+++ b/tests/wpt/web-platform-tests/html/semantics/forms/the-label-element/clicking-noninteractive-unlabelable-content.html
@@ -17,6 +17,16 @@
   <input type=hidden>
   <object></object>
   <video></video>
+
+  <!-- These are considered interactive content for the purpose of <label> in a
+  previous version of the HTML Standard, but no longer. -->
+  <a tabindex=""></a>
+  <audio tabindex=""></audio>
+  <div tabindex=""></div>
+  <img tabindex="">
+  <input type=hidden tabindex="">
+  <object tabindex=""></object>
+  <video tabindex=""></video>
 </template>
 
 <script>
diff --git a/tests/wpt/web-platform-tests/preload/subresource-integrity-partial-image.html b/tests/wpt/web-platform-tests/preload/subresource-integrity-partial-image.html
new file mode 100644
index 00000000000..3abc8399219
--- /dev/null
+++ b/tests/wpt/web-platform-tests/preload/subresource-integrity-partial-image.html
@@ -0,0 +1,28 @@
+<!DOCTYPE html>
+<meta charset="utf-8">
+<title>Subresource Integrity Check + preload + partial image rendering</title>
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+
+<script>
+// https://crbug.com/1058045: Chromium crashed when:
+// 1. <link rel="preload" as="image" integrity="..." href="url">
+//    (strictly speaking the preload scannner) starts preloading the image,
+//    and the image url takes some time for loading,
+// 2. <img> loads the same URL and renders the partial image after some image
+//    data is received but before fully loaded, and then
+// 3. the image is loaded and integrity check is done.
+
+const t = async_test(
+  "<link rel='image'> with progressive image shouldn't crash");
+
+</script>
+
+<link
+  rel="preload"
+  as="image"
+  integrity="sha256-47DEQpj8HBSa+/TImW+5JCeuQeRkm5NMpJWZG3hSuFU="
+  href="/element-timing/resources/progressive-image.py?name=square100.png&numInitial=7500&sleep=1000">
+<img src="/element-timing/resources/progressive-image.py?name=square100.png&numInitial=7500&sleep=1000"
+  onload="t.step_func_done()()"
+  onerror="t.unreached_func('image should load because SRI is not checked')()">
diff --git a/tests/wpt/web-platform-tests/webdriver/tests/add_cookie/add.py b/tests/wpt/web-platform-tests/webdriver/tests/add_cookie/add.py
index c1a886aafa7..30804c1dd8e 100644
--- a/tests/wpt/web-platform-tests/webdriver/tests/add_cookie/add.py
+++ b/tests/wpt/web-platform-tests/webdriver/tests/add_cookie/add.py
@@ -1,4 +1,5 @@
 from datetime import datetime, timedelta
+from six import text_type
 
 from webdriver.transport import Response
 
@@ -59,11 +60,11 @@ def test_add_domain_cookie(session, url, server_config):
 
     cookie = session.cookies("hello")
     assert "domain" in cookie
-    assert isinstance(cookie["domain"], basestring)
+    assert isinstance(cookie["domain"], text_type)
     assert "name" in cookie
-    assert isinstance(cookie["name"], basestring)
+    assert isinstance(cookie["name"], text_type)
     assert "value" in cookie
-    assert isinstance(cookie["value"], basestring)
+    assert isinstance(cookie["value"], text_type)
 
     assert cookie["name"] == "hello"
     assert cookie["value"] == "world"
@@ -89,11 +90,11 @@ def test_add_cookie_for_ip(session, url, server_config, configuration):
 
     cookie = session.cookies("hello")
     assert "name" in cookie
-    assert isinstance(cookie["name"], basestring)
+    assert isinstance(cookie["name"], text_type)
     assert "value" in cookie
-    assert isinstance(cookie["value"], basestring)
+    assert isinstance(cookie["value"], text_type)
     assert "domain" in cookie
-    assert isinstance(cookie["domain"], basestring)
+    assert isinstance(cookie["domain"], text_type)
 
     assert cookie["name"] == "hello"
     assert cookie["value"] == "world"
@@ -118,9 +119,9 @@ def test_add_non_session_cookie(session, url):
 
     cookie = session.cookies("hello")
     assert "name" in cookie
-    assert isinstance(cookie["name"], basestring)
+    assert isinstance(cookie["name"], text_type)
     assert "value" in cookie
-    assert isinstance(cookie["value"], basestring)
+    assert isinstance(cookie["value"], text_type)
     assert "expiry" in cookie
     assert isinstance(cookie["expiry"], int)
 
@@ -143,9 +144,9 @@ def test_add_session_cookie(session, url):
 
     cookie = session.cookies("hello")
     assert "name" in cookie
-    assert isinstance(cookie["name"], basestring)
+    assert isinstance(cookie["name"], text_type)
     assert "value" in cookie
-    assert isinstance(cookie["value"], basestring)
+    assert isinstance(cookie["value"], text_type)
     if "expiry" in cookie:
         assert cookie.get("expiry") is None
 
@@ -168,11 +169,11 @@ def test_add_session_cookie_with_leading_dot_character_in_domain(session, url, s
 
     cookie = session.cookies("hello")
     assert "name" in cookie
-    assert isinstance(cookie["name"], basestring)
+    assert isinstance(cookie["name"], text_type)
     assert "value" in cookie
-    assert isinstance(cookie["value"], basestring)
+    assert isinstance(cookie["value"], text_type)
     assert "domain" in cookie
-    assert isinstance(cookie["domain"], basestring)
+    assert isinstance(cookie["domain"], text_type)
 
     assert cookie["name"] == "hello"
     assert cookie["value"] == "world"
diff --git a/tests/wpt/web-platform-tests/webdriver/tests/execute_async_script/collections.py b/tests/wpt/web-platform-tests/webdriver/tests/execute_async_script/collections.py
index 14848da7e29..484a247cffd 100644
--- a/tests/wpt/web-platform-tests/webdriver/tests/execute_async_script/collections.py
+++ b/tests/wpt/web-platform-tests/webdriver/tests/execute_async_script/collections.py
@@ -1,5 +1,7 @@
 import os
 
+from six import text_type
+
 from tests.support.asserts import assert_same_element, assert_success
 from tests.support.inline import inline
 
@@ -52,7 +54,7 @@ def test_file_list(session, tmpdir):
     for expected, actual in zip(files, value):
         assert isinstance(actual, dict)
         assert "name" in actual
-        assert isinstance(actual["name"], basestring)
+        assert isinstance(actual["name"], text_type)
         assert os.path.basename(str(expected)) == actual["name"]
 
 
diff --git a/tests/wpt/web-platform-tests/webdriver/tests/execute_script/collections.py b/tests/wpt/web-platform-tests/webdriver/tests/execute_script/collections.py
index f939713c806..be0b3a018c5 100644
--- a/tests/wpt/web-platform-tests/webdriver/tests/execute_script/collections.py
+++ b/tests/wpt/web-platform-tests/webdriver/tests/execute_script/collections.py
@@ -1,5 +1,7 @@
 import os
 
+from six import text_type
+
 from tests.support.asserts import assert_same_element, assert_success
 from tests.support.inline import inline
 
@@ -45,7 +47,7 @@ def test_file_list(session, tmpdir):
     for expected, actual in zip(files, value):
         assert isinstance(actual, dict)
         assert "name" in actual
-        assert isinstance(actual["name"], basestring)
+        assert isinstance(actual["name"], text_type)
         assert os.path.basename(str(expected)) == actual["name"]
 
 
diff --git a/tests/wpt/web-platform-tests/webdriver/tests/get_alert_text/get.py b/tests/wpt/web-platform-tests/webdriver/tests/get_alert_text/get.py
index d6fdda2d1ed..ad0058e0326 100644
--- a/tests/wpt/web-platform-tests/webdriver/tests/get_alert_text/get.py
+++ b/tests/wpt/web-platform-tests/webdriver/tests/get_alert_text/get.py
@@ -1,3 +1,5 @@
+from six import text_type
+
 from webdriver.error import NoSuchAlertException
 
 from tests.support.asserts import assert_error, assert_success
@@ -27,7 +29,7 @@ def test_get_alert_text(session):
     assert isinstance(response.body, dict)
     assert "value" in response.body
     alert_text = response.body["value"]
-    assert isinstance(alert_text, basestring)
+    assert isinstance(alert_text, text_type)
     assert alert_text == "Hello"
 
 
@@ -38,7 +40,7 @@ def test_get_confirm_text(session):
     assert isinstance(response.body, dict)
     assert "value" in response.body
     confirm_text = response.body["value"]
-    assert isinstance(confirm_text, basestring)
+    assert isinstance(confirm_text, text_type)
     assert confirm_text == "Hello"
 
 
@@ -49,7 +51,7 @@ def test_get_prompt_text(session):
     assert isinstance(response.body, dict)
     assert "value" in response.body
     prompt_text = response.body["value"]
-    assert isinstance(prompt_text, basestring)
+    assert isinstance(prompt_text, text_type)
     assert prompt_text == "Enter Your Name: "
 
 
diff --git a/tests/wpt/web-platform-tests/webdriver/tests/get_current_url/get.py b/tests/wpt/web-platform-tests/webdriver/tests/get_current_url/get.py
index 39c28c61216..c22e3d410c3 100644
--- a/tests/wpt/web-platform-tests/webdriver/tests/get_current_url/get.py
+++ b/tests/wpt/web-platform-tests/webdriver/tests/get_current_url/get.py
@@ -1,3 +1,5 @@
+from six import text_type
+
 from tests.support import platform_name
 from tests.support.inline import inline
 from tests.support.asserts import assert_error, assert_success
@@ -31,7 +33,7 @@ def test_get_current_url_payload(session):
 
     response = get_current_url(session)
     assert response.status == 200
-    assert isinstance(response.body["value"], basestring)
+    assert isinstance(response.body["value"], text_type)
 
 
 def test_get_current_url_special_pages(session):
diff --git a/tests/wpt/web-platform-tests/webdriver/tests/get_named_cookie/get.py b/tests/wpt/web-platform-tests/webdriver/tests/get_named_cookie/get.py
index 9ea29c8994e..1fd5f9f1449 100644
--- a/tests/wpt/web-platform-tests/webdriver/tests/get_named_cookie/get.py
+++ b/tests/wpt/web-platform-tests/webdriver/tests/get_named_cookie/get.py
@@ -1,4 +1,6 @@
 from datetime import datetime, timedelta
+from six import integer_types, text_type
+
 
 from tests.support.asserts import assert_error, assert_success
 from tests.support.helpers import clear_all_cookies
@@ -28,13 +30,13 @@ def test_get_named_session_cookie(session, url):
     # table for cookie conversion
     # https://w3c.github.io/webdriver/webdriver-spec.html#dfn-table-for-cookie-conversion
     assert "name" in cookie
-    assert isinstance(cookie["name"], basestring)
+    assert isinstance(cookie["name"], text_type)
     assert "value" in cookie
-    assert isinstance(cookie["value"], basestring)
+    assert isinstance(cookie["value"], text_type)
     assert "path" in cookie
-    assert isinstance(cookie["path"], basestring)
+    assert isinstance(cookie["path"], text_type)
     assert "domain" in cookie
-    assert isinstance(cookie["domain"], basestring)
+    assert isinstance(cookie["domain"], text_type)
     assert "secure" in cookie
     assert isinstance(cookie["secure"], bool)
     assert "httpOnly" in cookie
@@ -60,11 +62,11 @@ def test_get_named_cookie(session, url):
     assert isinstance(cookie, dict)
 
     assert "name" in cookie
-    assert isinstance(cookie["name"], basestring)
+    assert isinstance(cookie["name"], text_type)
     assert "value" in cookie
-    assert isinstance(cookie["value"], basestring)
+    assert isinstance(cookie["value"], text_type)
     assert "expiry" in cookie
-    assert isinstance(cookie["expiry"], (int, long))
+    assert isinstance(cookie["expiry"], integer_types)
 
     assert cookie["name"] == "foo"
     assert cookie["value"] == "bar"
@@ -99,9 +101,9 @@ def test_duplicated_cookie(session, url, server_config):
     assert isinstance(cookie, dict)
 
     assert "name" in cookie
-    assert isinstance(cookie["name"], basestring)
+    assert isinstance(cookie["name"], text_type)
     assert "value" in cookie
-    assert isinstance(cookie["value"], basestring)
+    assert isinstance(cookie["value"], text_type)
 
     assert cookie["name"] == new_cookie["name"]
     assert cookie["value"] == "newworld"
diff --git a/tests/wpt/web-platform-tests/webdriver/tests/new_session/create_alwaysMatch.py b/tests/wpt/web-platform-tests/webdriver/tests/new_session/create_alwaysMatch.py
index 097764e4a99..a4cc9efc02e 100644
--- a/tests/wpt/web-platform-tests/webdriver/tests/new_session/create_alwaysMatch.py
+++ b/tests/wpt/web-platform-tests/webdriver/tests/new_session/create_alwaysMatch.py
@@ -2,7 +2,7 @@
 
 import pytest
 
-from conftest import product, flatten
+from .conftest import product, flatten
 
 from tests.support.asserts import assert_success
 from tests.new_session.support.create import valid_data
diff --git a/tests/wpt/web-platform-tests/webdriver/tests/new_session/create_firstMatch.py b/tests/wpt/web-platform-tests/webdriver/tests/new_session/create_firstMatch.py
index f00f6042b08..ec671530f79 100644
--- a/tests/wpt/web-platform-tests/webdriver/tests/new_session/create_firstMatch.py
+++ b/tests/wpt/web-platform-tests/webdriver/tests/new_session/create_firstMatch.py
@@ -2,7 +2,7 @@
 
 import pytest
 
-from conftest import product, flatten
+from .conftest import product, flatten
 
 
 from tests.support.asserts import assert_success
diff --git a/tests/wpt/web-platform-tests/webdriver/tests/new_session/invalid_capabilities.py b/tests/wpt/web-platform-tests/webdriver/tests/new_session/invalid_capabilities.py
index f31ce3b8b6f..afdcea0daf7 100644
--- a/tests/wpt/web-platform-tests/webdriver/tests/new_session/invalid_capabilities.py
+++ b/tests/wpt/web-platform-tests/webdriver/tests/new_session/invalid_capabilities.py
@@ -1,6 +1,6 @@
 import pytest
 
-from conftest import product, flatten
+from .conftest import product, flatten
 
 from tests.new_session.support.create import invalid_data, invalid_extensions
 from tests.support.asserts import assert_error
diff --git a/tests/wpt/web-platform-tests/webdriver/tests/new_session/response.py b/tests/wpt/web-platform-tests/webdriver/tests/new_session/response.py
index 16c526ae10b..dc132899881 100644
--- a/tests/wpt/web-platform-tests/webdriver/tests/new_session/response.py
+++ b/tests/wpt/web-platform-tests/webdriver/tests/new_session/response.py
@@ -1,28 +1,29 @@
 import uuid
-
 import pytest
 
+from six import text_type
+
 from tests.support.asserts import assert_success
 
 
 def test_sessionid(new_session, add_browser_capabilities):
     response, _ = new_session({"capabilities": {"alwaysMatch": add_browser_capabilities({})}})
     value = assert_success(response)
-    assert isinstance(value["sessionId"], basestring)
+    assert isinstance(value["sessionId"], text_type)
     uuid.UUID(hex=value["sessionId"])
 
 
 @pytest.mark.parametrize("capability, type", [
-    ("browserName", basestring),
-    ("browserVersion", basestring),
-    ("platformName", basestring),
+    ("browserName", text_type),
+    ("browserVersion", text_type),
+    ("platformName", text_type),
     ("acceptInsecureCerts", bool),
-    ("pageLoadStrategy", basestring),
+    ("pageLoadStrategy", text_type),
     ("proxy", dict),
     ("setWindowRect", bool),
     ("timeouts", dict),
     ("strictFileInteractability", bool),
-    ("unhandledPromptBehavior", basestring),
+    ("unhandledPromptBehavior", text_type),
 ])
 def test_capability_type(session, capability, type):
     assert isinstance(session.capabilities, dict)
diff --git a/tests/wpt/web-platform-tests/webdriver/tests/perform_actions/support/keys.py b/tests/wpt/web-platform-tests/webdriver/tests/perform_actions/support/keys.py
index d4072f5a3f3..26825f04148 100644
--- a/tests/wpt/web-platform-tests/webdriver/tests/perform_actions/support/keys.py
+++ b/tests/wpt/web-platform-tests/webdriver/tests/perform_actions/support/keys.py
@@ -17,9 +17,10 @@
 
 """The Keys implementation."""
 
-from inspect import getmembers
 import sys
 
+from inspect import getmembers
+from six import text_type
 
 class Keys(object):
     """
@@ -105,7 +106,7 @@ class Keys(object):
     R_DELETE = u"\uE05D"
 
 
-ALL_KEYS = getmembers(Keys, lambda x: type(x) == unicode)
+ALL_KEYS = getmembers(Keys, lambda x: type(x) == text_type)
 
 ALL_EVENTS = {
     "ADD": {
diff --git a/tests/wpt/web-platform-tests/webdriver/tests/status/status.py b/tests/wpt/web-platform-tests/webdriver/tests/status/status.py
index f0df16a1ee1..1f0f1bc4fe7 100644
--- a/tests/wpt/web-platform-tests/webdriver/tests/status/status.py
+++ b/tests/wpt/web-platform-tests/webdriver/tests/status/status.py
@@ -1,5 +1,7 @@
 import json
 
+from six import text_type
+
 from tests.support.asserts import assert_success
 
 
@@ -16,7 +18,7 @@ def test_get_status_no_session(http):
         value = parsed_obj["value"]
 
         assert value["ready"] in [True, False]
-        assert isinstance(value["message"], basestring)
+        assert isinstance(value["message"], text_type)
 
 
 def test_status_with_session_running_on_endpoint_node(session):
diff --git a/tests/wpt/web-platform-tests/webdriver/tests/support/asserts.py b/tests/wpt/web-platform-tests/webdriver/tests/support/asserts.py
index f65137463b4..5bd7f5b38e7 100644
--- a/tests/wpt/web-platform-tests/webdriver/tests/support/asserts.py
+++ b/tests/wpt/web-platform-tests/webdriver/tests/support/asserts.py
@@ -2,7 +2,7 @@ import base64
 import imghdr
 import struct
 
-from six import PY3
+from six import ensure_binary, text_type, PY3
 
 from webdriver import Element, NoSuchAlertException, WebDriverException
 
@@ -52,8 +52,8 @@ def assert_error(response, error_code):
     assert response.status == errors[error_code]
     assert "value" in response.body
     assert response.body["value"]["error"] == error_code
-    assert isinstance(response.body["value"]["message"], basestring)
-    assert isinstance(response.body["value"]["stacktrace"], basestring)
+    assert isinstance(response.body["value"]["message"], text_type)
+    assert isinstance(response.body["value"]["stacktrace"], text_type)
     assert_response_headers(response.headers)
 
 
@@ -221,6 +221,6 @@ def assert_move_to_coordinates(point, target, events):
 
 def assert_png(screenshot):
     """Test that screenshot is a Base64 encoded PNG file."""
-    image = base64.decodestring(screenshot)
+    image = base64.decodestring(ensure_binary(screenshot))
     mime_type = imghdr.what("", image)
     assert mime_type == "png", "Expected image to be PNG, but it was {}".format(mime_type)
diff --git a/tests/wpt/web-platform-tests/webdriver/tests/support/authentication.py b/tests/wpt/web-platform-tests/webdriver/tests/support/authentication.py
index 6f880f3c851..1e88a9e730d 100644
--- a/tests/wpt/web-platform-tests/webdriver/tests/support/authentication.py
+++ b/tests/wpt/web-platform-tests/webdriver/tests/support/authentication.py
@@ -1,4 +1,4 @@
-import urllib
+from six.moves.urllib.parse import urlencode
 
 
 def basic_authentication(username=None, password=None, protocol="http"):
@@ -8,7 +8,7 @@ def basic_authentication(username=None, password=None, protocol="http"):
     query = {}
 
     return build_url("/webdriver/tests/support/authentication.py",
-                     query=urllib.urlencode(query),
+                     query=urlencode(query),
                      protocol=protocol)
 
 
diff --git a/tests/wpt/web-platform-tests/webdriver/tests/support/fixtures.py b/tests/wpt/web-platform-tests/webdriver/tests/support/fixtures.py
index ab2aaf4e75d..80ccfddf3d1 100644
--- a/tests/wpt/web-platform-tests/webdriver/tests/support/fixtures.py
+++ b/tests/wpt/web-platform-tests/webdriver/tests/support/fixtures.py
@@ -1,11 +1,14 @@
 import copy
 import json
 import os
-import urlparse
 
 import pytest
 import webdriver
 
+from six import string_types
+
+from six.moves.urllib.parse import urlunsplit
+
 from tests.support import defaults
 from tests.support.helpers import cleanup_session
 from tests.support.http_request import HTTPRequest
@@ -172,7 +175,7 @@ def url(server_config):
         domain = server_config["domains"][domain][subdomain]
         port = server_config["ports"][protocol][0]
         host = "{0}:{1}".format(domain, port)
-        return urlparse.urlunsplit((protocol, host, path, query, fragment))
+        return urlunsplit((protocol, host, path, query, fragment))
 
     inner.__name__ = "url"
     return inner
@@ -191,7 +194,7 @@ def create_dialog(session):
         if text is None:
             text = ""
 
-        assert isinstance(text, basestring), "`text` parameter must be a string"
+        assert isinstance(text, string_types), "`text` parameter must be a string"
 
         # Script completes itself when the user prompt has been opened.
         # For prompt() dialogs, add a value for the 'default' argument,
diff --git a/tests/wpt/web-platform-tests/webdriver/tests/support/http_request.py b/tests/wpt/web-platform-tests/webdriver/tests/support/http_request.py
index 5e46d97017e..895d1319ac0 100644
--- a/tests/wpt/web-platform-tests/webdriver/tests/support/http_request.py
+++ b/tests/wpt/web-platform-tests/webdriver/tests/support/http_request.py
@@ -1,9 +1,10 @@
 import contextlib
-import httplib
 import json
 
 from six import text_type
 
+from six.moves.http_client import HTTPConnection
+
 
 class HTTPRequest(object):
     def __init__(self, host, port):
@@ -33,7 +34,7 @@ class HTTPRequest(object):
             if isinstance(payload, text_type):
                 payload = body.encode("utf-8")
 
-        conn = httplib.HTTPConnection(self.host, self.port)
+        conn = HTTPConnection(self.host, self.port)
         try:
             conn.request(method, path, payload)
             yield conn.getresponse()
diff --git a/tests/wpt/web-platform-tests/webdriver/tests/support/image.py b/tests/wpt/web-platform-tests/webdriver/tests/support/image.py
index 81dd933943f..6149ccccbe3 100644
--- a/tests/wpt/web-platform-tests/webdriver/tests/support/image.py
+++ b/tests/wpt/web-platform-tests/webdriver/tests/support/image.py
@@ -2,11 +2,13 @@ import base64
 import math
 import struct
 
+from six import ensure_binary
+
 from tests.support.asserts import assert_png
 
 
 def png_dimensions(screenshot):
     assert_png(screenshot)
-    image = base64.decodestring(screenshot)
+    image = base64.decodestring(ensure_binary(screenshot))
     width, height = struct.unpack(">LL", image[16:24])
     return int(width), int(height)
diff --git a/tests/wpt/web-platform-tests/webdriver/tests/support/inline.py b/tests/wpt/web-platform-tests/webdriver/tests/support/inline.py
index b65b9cb8b11..15bc26e54c6 100644
--- a/tests/wpt/web-platform-tests/webdriver/tests/support/inline.py
+++ b/tests/wpt/web-platform-tests/webdriver/tests/support/inline.py
@@ -1,6 +1,6 @@
 """Helpers for inlining extracts of documents in tests."""
 
-import urllib
+from six.moves.urllib.parse import urlencode
 
 
 BOILERPLATES = {
@@ -58,7 +58,7 @@ def inline(src, doctype="html", mime=None, charset=None, **kwargs):
     query = {"doc": doc, "mime": mime, "charset": charset}
     return build_url(
         "/webdriver/tests/support/inline.py",
-        query=urllib.urlencode(query),
+        query=urlencode(query),
         **kwargs)
 
 
diff --git a/tests/wpt/web-platform-tests/webdriver/tests/switch_to_frame/cross_origin.py b/tests/wpt/web-platform-tests/webdriver/tests/switch_to_frame/cross_origin.py
index 4425a3ab901..905f1eb56dc 100644
--- a/tests/wpt/web-platform-tests/webdriver/tests/switch_to_frame/cross_origin.py
+++ b/tests/wpt/web-platform-tests/webdriver/tests/switch_to_frame/cross_origin.py
@@ -1,4 +1,4 @@
-from urlparse import urlparse
+from six.moves.urllib.parse import urlparse
 
 import webdriver.protocol as protocol
 
diff --git a/tests/wpt/web-platform-tests/webdriver/tests/switch_to_frame/switch.py b/tests/wpt/web-platform-tests/webdriver/tests/switch_to_frame/switch.py
index 67b855a96d9..f9b0e6fc1fc 100644
--- a/tests/wpt/web-platform-tests/webdriver/tests/switch_to_frame/switch.py
+++ b/tests/wpt/web-platform-tests/webdriver/tests/switch_to_frame/switch.py
@@ -18,7 +18,7 @@ def switch_to_frame(session, frame):
 
 
 def frameset(*docs):
-    frames = map(lambda doc: "<frame src='{}'></frame>".format(inline(doc)), docs)
+    frames = list(map(lambda doc: "<frame src='{}'></frame>".format(inline(doc)), docs))
     return "<frameset rows='{}'>\n{}</frameset>".format(len(frames) * "*,", "\n".join(frames))
 
 
diff --git a/tests/wpt/web-platform-tests/webxr/hit-test/xrRay_constructor.https.html b/tests/wpt/web-platform-tests/webxr/hit-test/xrRay_constructor.https.html
index 08f20142e38..d4d727785f1 100644
--- a/tests/wpt/web-platform-tests/webxr/hit-test/xrRay_constructor.https.html
+++ b/tests/wpt/web-platform-tests/webxr/hit-test/xrRay_constructor.https.html
@@ -91,25 +91,23 @@ let constructor_tests = function() {
   {
     // Check that we throw exception on direction too close to 0,0,0:
     let originDict = {x : 10.0, y : 10.0, z : 10.0, w : 1.0};
-    let directionDict = {x : 0.0, y : 0.0, z : 0.0, w : 0.0};
+    let directionDict = {x : 1.0, y : 0.0, z : 0.0, w : 0.0};
 
-    try {
-      let xrRay = new XRRay(
+    assert_throws_js(TypeError, () => new XRRay(
         DOMPoint.fromPoint(originDict),
-        DOMPoint.fromPoint(directionDict));
+        DOMPoint.fromPoint({x : 0.0, y : 0.0, z : 0.0, w : 0.0})
+    ), "Constructor should throw for zero direction");
 
-      assert(false, "origin-custom-direction-zero:exception not thrown");
-    }
-    catch(e)
-    {
-      if(e instanceof DOMException) {
-        assert_equals(e.name, "InvalidStateError", "origin-custom-direction-zero:incorrect DOM exception thrown");
-      } else {
-        assert(false, "origin-custom-direction-zero:other exception thrown: " + e);
-      }
-    }
+    assert_throws_js(TypeError, () => new XRRay(
+        DOMPoint.fromPoint(originDict),
+        DOMPoint.fromPoint({x : 1.0, y : 0.0, z : 0.0, w : 0.5})
+    ), "Constructor should throw for nonzero direction w coordinate");
+
+    assert_throws_js(TypeError, () => new XRRay(
+        DOMPoint.fromPoint({x : 10.0, y : 10.0, z : 10.0, w : 0.5}),
+        DOMPoint.fromPoint(directionDict)
+    ), "Constructor should throw for non-1 origin w coordinate");
   }
-
   //
   // Constructor 2 - from rigid transform.
   //
diff --git a/tests/wpt/web-platform-tests/webxr/resources/webxr_test_constants_fake_world.js b/tests/wpt/web-platform-tests/webxr/resources/webxr_test_constants_fake_world.js
index 4e2adc633fd..7e428e21550 100644
--- a/tests/wpt/web-platform-tests/webxr/resources/webxr_test_constants_fake_world.js
+++ b/tests/wpt/web-platform-tests/webxr/resources/webxr_test_constants_fake_world.js
@@ -29,26 +29,26 @@ function createFakeWorld(
   // Faces:
   const FRONT_WALL_AND_FLOOR_FACES = [
     // Front wall:
-    [BOTTOM_LEFT_FRONT, BOTTOM_RIGHT_FRONT, TOP_RIGHT_FRONT],
-    [BOTTOM_LEFT_FRONT, TOP_RIGHT_FRONT, TOP_LEFT_FRONT],
+    { vertices: [BOTTOM_LEFT_FRONT, BOTTOM_RIGHT_FRONT, TOP_RIGHT_FRONT] },
+    { vertices: [BOTTOM_LEFT_FRONT, TOP_RIGHT_FRONT, TOP_LEFT_FRONT] },
     // Floor:
-    [BOTTOM_LEFT_FRONT, BOTTOM_RIGHT_FRONT, BOTTOM_RIGHT_BACK],
-    [BOTTOM_LEFT_FRONT, BOTTOM_LEFT_BACK, BOTTOM_RIGHT_BACK],
+    { vertices: [BOTTOM_LEFT_FRONT, BOTTOM_RIGHT_FRONT, BOTTOM_RIGHT_BACK] },
+    { vertices: [BOTTOM_LEFT_FRONT, BOTTOM_LEFT_BACK, BOTTOM_RIGHT_BACK] },
   ];
 
   const CEILING_FACES = [
     // Ceiling:
-    [TOP_LEFT_FRONT, TOP_RIGHT_FRONT, TOP_RIGHT_BACK],
-    [TOP_LEFT_FRONT, TOP_LEFT_BACK, TOP_RIGHT_BACK],
+    { vertices: [TOP_LEFT_FRONT, TOP_RIGHT_FRONT, TOP_RIGHT_BACK] },
+    { vertices: [TOP_LEFT_FRONT, TOP_LEFT_BACK, TOP_RIGHT_BACK] },
   ];
 
   const SIDE_WALLS_FACES = [
     // Left:
-    [BOTTOM_LEFT_FRONT, TOP_LEFT_FRONT, TOP_LEFT_BACK],
-    [BOTTOM_LEFT_FRONT, BOTTOM_LEFT_BACK, TOP_LEFT_BACK],
+    { vertices: [BOTTOM_LEFT_FRONT, TOP_LEFT_FRONT, TOP_LEFT_BACK] },
+    { vertices: [BOTTOM_LEFT_FRONT, BOTTOM_LEFT_BACK, TOP_LEFT_BACK] },
     // Right:
-    [BOTTOM_RIGHT_FRONT, TOP_RIGHT_FRONT, TOP_RIGHT_BACK],
-    [BOTTOM_RIGHT_FRONT, BOTTOM_RIGHT_BACK, TOP_RIGHT_BACK],
+    { vertices: [BOTTOM_RIGHT_FRONT, TOP_RIGHT_FRONT, TOP_RIGHT_BACK] },
+    { vertices: [BOTTOM_RIGHT_FRONT, BOTTOM_RIGHT_BACK, TOP_RIGHT_BACK] },
   ];
 
   // Regions: