diff --git a/tests/wpt/metadata-layout-2020/css/CSS2/floats/hit-test-floats-003.html.ini b/tests/wpt/metadata-layout-2020/css/CSS2/floats/hit-test-floats-003.html.ini
deleted file mode 100644
index f29da48a2a0..00000000000
--- a/tests/wpt/metadata-layout-2020/css/CSS2/floats/hit-test-floats-003.html.ini
+++ /dev/null
@@ -1,4 +0,0 @@
-[hit-test-floats-003.html]
-  [Miss float below something else]
-    expected: FAIL
-
diff --git a/tests/wpt/metadata-layout-2020/css/CSS2/floats/hit-test-floats-004.html.ini b/tests/wpt/metadata-layout-2020/css/CSS2/floats/hit-test-floats-004.html.ini
deleted file mode 100644
index 4bfb0c2053a..00000000000
--- a/tests/wpt/metadata-layout-2020/css/CSS2/floats/hit-test-floats-004.html.ini
+++ /dev/null
@@ -1,4 +0,0 @@
-[hit-test-floats-004.html]
-  [Miss float below something else]
-    expected: FAIL
-
diff --git a/tests/wpt/metadata-layout-2020/css/CSS2/floats/hit-test-floats-005.html.ini b/tests/wpt/metadata-layout-2020/css/CSS2/floats/hit-test-floats-005.html.ini
new file mode 100644
index 00000000000..baa9f1a7541
--- /dev/null
+++ b/tests/wpt/metadata-layout-2020/css/CSS2/floats/hit-test-floats-005.html.ini
@@ -0,0 +1,4 @@
+[hit-test-floats-005.html]
+  [Miss clipped float]
+    expected: FAIL
+
diff --git a/tests/wpt/metadata-layout-2020/css/CSS2/linebox/inline-negative-margin-001.html.ini b/tests/wpt/metadata-layout-2020/css/CSS2/linebox/inline-negative-margin-001.html.ini
index ace25673ae5..c53734dcdd7 100644
--- a/tests/wpt/metadata-layout-2020/css/CSS2/linebox/inline-negative-margin-001.html.ini
+++ b/tests/wpt/metadata-layout-2020/css/CSS2/linebox/inline-negative-margin-001.html.ini
@@ -11,33 +11,6 @@
   [[data-expected-height\] 2]
     expected: FAIL
 
-  [[data-expected-height\] 1]
-    expected: FAIL
-
-  [[data-expected-height\] 10]
-    expected: FAIL
-
-  [[data-expected-height\] 2]
-    expected: FAIL
-
-  [[data-expected-height\] 5]
-    expected: FAIL
-
-  [[data-expected-height\] 6]
-    expected: FAIL
-
-  [[data-expected-height\] 9]
-    expected: FAIL
-
-  [[data-expected-height\] 8]
-    expected: FAIL
-
-  [[data-expected-height\] 13]
-    expected: FAIL
-
-  [[data-expected-height\] 12]
-    expected: FAIL
-
-  [[data-expected-height\] 11]
+  [[data-expected-height\] 4]
     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/cssom-view/CaretPosition-001.html.ini b/tests/wpt/metadata-layout-2020/css/cssom-view/CaretPosition-001.html.ini
new file mode 100644
index 00000000000..4c79907309b
--- /dev/null
+++ b/tests/wpt/metadata-layout-2020/css/cssom-view/CaretPosition-001.html.ini
@@ -0,0 +1,4 @@
+[CaretPosition-001.html]
+  [Element at (400, 100)]
+    expected: FAIL
+
diff --git a/tests/wpt/metadata-layout-2020/css/cssom-view/MediaQueryList-addListener-removeListener.html.ini b/tests/wpt/metadata-layout-2020/css/cssom-view/MediaQueryList-addListener-removeListener.html.ini
index 628b1fab770..c884dc82eab 100644
--- a/tests/wpt/metadata-layout-2020/css/cssom-view/MediaQueryList-addListener-removeListener.html.ini
+++ b/tests/wpt/metadata-layout-2020/css/cssom-view/MediaQueryList-addListener-removeListener.html.ini
@@ -2,3 +2,6 @@
   [listeners are called when <iframe> is resized]
     expected: FAIL
 
+  [listeners are called correct number of times]
+    expected: FAIL
+
diff --git a/tests/wpt/metadata-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/elementsFromPoint-iframes.html.ini b/tests/wpt/metadata-layout-2020/css/cssom-view/elementsFromPoint-iframes.html.ini
index 171592fc08f..6ef8bb1049f 100644
--- a/tests/wpt/metadata-layout-2020/css/cssom-view/elementsFromPoint-iframes.html.ini
+++ b/tests/wpt/metadata-layout-2020/css/cssom-view/elementsFromPoint-iframes.html.ini
@@ -2,3 +2,6 @@
   [elementsFromPoint on the root document for points in iframe elements]
     expected: FAIL
 
+  [elementsFromPoint on inner documents]
+    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 a7ddeaab5a4..946fc6a9dbf 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
@@ -315,15 +315,6 @@
   [<iframe>: separate response Content-Type: text/html */*]
     expected: FAIL
 
-  [<iframe>: separate response Content-Type: 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>: combined response Content-Type: text/html */*;charset=gbk]
     expected: FAIL
 
@@ -336,6 +327,6 @@
   [<iframe>: separate response Content-Type: text/html;" \\" text/plain]
     expected: FAIL
 
-  [<iframe>: combined response Content-Type: text/html;x=" text/plain]
+  [<iframe>: combined response Content-Type: text/html;" \\" 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..e67f0406fc3 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
@@ -53,6 +53,3 @@
   [combined text/javascript ]
     expected: FAIL
 
-  [separate text/javascript x/x]
-    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 30e1b851fd4..c7ffe03c4ae 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
@@ -11,3 +11,9 @@
   [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%22nosniFF%22]
+    expected: FAIL
+
+  [X-Content-Type-Options%3A%20%40%23%24%23%25%25%26%5E%26%5E*()()11!%2Cnosniff]
+    expected: FAIL
+
diff --git a/tests/wpt/metadata-layout-2020/html/browsers/history/the-history-interface/traverse_the_history_1.html.ini b/tests/wpt/metadata-layout-2020/html/browsers/history/the-history-interface/traverse_the_history_1.html.ini
deleted file mode 100644
index 87b07c3e670..00000000000
--- a/tests/wpt/metadata-layout-2020/html/browsers/history/the-history-interface/traverse_the_history_1.html.ini
+++ /dev/null
@@ -1,4 +0,0 @@
-[traverse_the_history_1.html]
-  [Multiple history traversals from the same task]
-    expected: FAIL
-
diff --git a/tests/wpt/metadata-layout-2020/html/browsers/history/the-history-interface/traverse_the_history_2.html.ini b/tests/wpt/metadata-layout-2020/html/browsers/history/the-history-interface/traverse_the_history_2.html.ini
new file mode 100644
index 00000000000..75d75b4cda2
--- /dev/null
+++ b/tests/wpt/metadata-layout-2020/html/browsers/history/the-history-interface/traverse_the_history_2.html.ini
@@ -0,0 +1,4 @@
+[traverse_the_history_2.html]
+  [Multiple history traversals, last would be aborted]
+    expected: FAIL
+
diff --git a/tests/wpt/metadata-layout-2020/html/browsers/origin/cross-origin-objects/cross-origin-objects-on-new-window.html.ini b/tests/wpt/metadata-layout-2020/html/browsers/origin/cross-origin-objects/cross-origin-objects-on-new-window.html.ini
deleted file mode 100644
index 735a9a75a2a..00000000000
--- a/tests/wpt/metadata-layout-2020/html/browsers/origin/cross-origin-objects/cross-origin-objects-on-new-window.html.ini
+++ /dev/null
@@ -1,2 +0,0 @@
-[cross-origin-objects-on-new-window.html]
-  expected: TIMEOUT
diff --git a/tests/wpt/metadata-layout-2020/html/browsers/windows/embedded-opener-remove-frame.html.ini b/tests/wpt/metadata-layout-2020/html/browsers/windows/embedded-opener-remove-frame.html.ini
index f29162631b3..9a85a905394 100644
--- a/tests/wpt/metadata-layout-2020/html/browsers/windows/embedded-opener-remove-frame.html.ini
+++ b/tests/wpt/metadata-layout-2020/html/browsers/windows/embedded-opener-remove-frame.html.ini
@@ -1,8 +1,7 @@
 [embedded-opener-remove-frame.html]
-  expected: CRASH
   [opener of discarded nested browsing context]
     expected: FAIL
 
   [opener of discarded auxiliary browsing context]
-    expected: TIMEOUT
+    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 f45aaafe1c5..ba183b6db32 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
@@ -1,16 +1,20 @@
 [supported-elements.html]
+  expected: TIMEOUT
   [Contenteditable element should support autofocus]
-    expected: FAIL
+    expected: TIMEOUT
 
   [Host element with delegatesFocus including no focusable descendants should be skipped]
-    expected: FAIL
+    expected: NOTRUN
 
   [Element with tabindex should support autofocus]
-    expected: FAIL
+    expected: NOTRUN
 
   [Area element should support autofocus]
-    expected: FAIL
+    expected: NOTRUN
 
   [Host element with delegatesFocus should support autofocus]
-    expected: FAIL
+    expected: NOTRUN
+
+  [Non-HTMLElement should not support autofocus]
+    expected: NOTRUN
 
diff --git a/tests/wpt/metadata-layout-2020/html/semantics/embedded-content/the-iframe-element/iframe_sandbox_popups_escaping-2.html.ini b/tests/wpt/metadata-layout-2020/html/semantics/embedded-content/the-iframe-element/iframe_sandbox_popups_escaping-2.html.ini
index e63fe7c263e..c6f45be1eb2 100644
--- a/tests/wpt/metadata-layout-2020/html/semantics/embedded-content/the-iframe-element/iframe_sandbox_popups_escaping-2.html.ini
+++ b/tests/wpt/metadata-layout-2020/html/semantics/embedded-content/the-iframe-element/iframe_sandbox_popups_escaping-2.html.ini
@@ -1,5 +1,5 @@
 [iframe_sandbox_popups_escaping-2.html]
-  expected: CRASH
+  expected: TIMEOUT
   [Check that popups from a sandboxed iframe escape the sandbox if\n       allow-popups-to-escape-sandbox is used]
     expected: TIMEOUT
 
diff --git a/tests/wpt/metadata-layout-2020/html/semantics/embedded-content/the-iframe-element/iframe_sandbox_popups_escaping-3.html.ini b/tests/wpt/metadata-layout-2020/html/semantics/embedded-content/the-iframe-element/iframe_sandbox_popups_escaping-3.html.ini
index 295031c1812..338d283eb0e 100644
--- a/tests/wpt/metadata-layout-2020/html/semantics/embedded-content/the-iframe-element/iframe_sandbox_popups_escaping-3.html.ini
+++ b/tests/wpt/metadata-layout-2020/html/semantics/embedded-content/the-iframe-element/iframe_sandbox_popups_escaping-3.html.ini
@@ -1,5 +1,4 @@
 [iframe_sandbox_popups_escaping-3.html]
-  expected: TIMEOUT
   [Check that popups from a sandboxed iframe escape the sandbox if\n       allow-popups-to-escape-sandbox is used]
-    expected: TIMEOUT
+    expected: FAIL
 
diff --git a/tests/wpt/metadata-layout-2020/html/semantics/embedded-content/the-iframe-element/iframe_sandbox_popups_nonescaping-2.html.ini b/tests/wpt/metadata-layout-2020/html/semantics/embedded-content/the-iframe-element/iframe_sandbox_popups_nonescaping-2.html.ini
index 0407f0cc2b7..9eb581fcf1f 100644
--- a/tests/wpt/metadata-layout-2020/html/semantics/embedded-content/the-iframe-element/iframe_sandbox_popups_nonescaping-2.html.ini
+++ b/tests/wpt/metadata-layout-2020/html/semantics/embedded-content/the-iframe-element/iframe_sandbox_popups_nonescaping-2.html.ini
@@ -1,5 +1,5 @@
 [iframe_sandbox_popups_nonescaping-2.html]
-  expected: TIMEOUT
+  expected: CRASH
   [Check that popups from a sandboxed iframe do not escape the sandbox]
     expected: NOTRUN
 
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 7d2b5231af2..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: CRASH
   [Check that popups from a sandboxed iframe do not escape the sandbox]
     expected: FAIL
 
diff --git a/tests/wpt/metadata-layout-2020/html/webappapis/dynamic-markup-insertion/document-write/module-static-import-delayed.html.ini b/tests/wpt/metadata-layout-2020/html/webappapis/dynamic-markup-insertion/document-write/module-static-import-delayed.html.ini
deleted file mode 100644
index fca4d908c89..00000000000
--- a/tests/wpt/metadata-layout-2020/html/webappapis/dynamic-markup-insertion/document-write/module-static-import-delayed.html.ini
+++ /dev/null
@@ -1,4 +0,0 @@
-[module-static-import-delayed.html]
-  [document.write in an imported module]
-    expected: FAIL
-
diff --git a/tests/wpt/metadata-layout-2020/html/webappapis/dynamic-markup-insertion/opening-the-input-stream/ignore-opens-during-unload.window.js.ini b/tests/wpt/metadata-layout-2020/html/webappapis/dynamic-markup-insertion/opening-the-input-stream/ignore-opens-during-unload.window.js.ini
index 58c9d7f8c0c..57744023f73 100644
--- a/tests/wpt/metadata-layout-2020/html/webappapis/dynamic-markup-insertion/opening-the-input-stream/ignore-opens-during-unload.window.js.ini
+++ b/tests/wpt/metadata-layout-2020/html/webappapis/dynamic-markup-insertion/opening-the-input-stream/ignore-opens-during-unload.window.js.ini
@@ -1,5 +1,5 @@
 [ignore-opens-during-unload.window.html]
-  expected: TIMEOUT
+  expected: CRASH
   [document.open should bail out when ignore-opens-during-unload is greater than 0 during visibilitychange event (open(parent) while unloading parent and child)]
     expected: TIMEOUT
 
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 5ddb9bfeff6..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
@@ -1,10 +1,9 @@
 [promise-job-entry.html]
-  expected: TIMEOUT
   [Fulfillment handler on fulfilled promise]
     expected: FAIL
 
   [Rejection handler on pending-then-rejected promise]
-    expected: TIMEOUT
+    expected: FAIL
 
   [Sanity check: this all works as expected with no promises involved]
     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/html/webappapis/scripting/processing-model-2/unhandled-promise-rejections/promise-rejection-events.html.ini b/tests/wpt/metadata-layout-2020/html/webappapis/scripting/processing-model-2/unhandled-promise-rejections/promise-rejection-events.html.ini
new file mode 100644
index 00000000000..d65177c2a5b
--- /dev/null
+++ b/tests/wpt/metadata-layout-2020/html/webappapis/scripting/processing-model-2/unhandled-promise-rejections/promise-rejection-events.html.ini
@@ -0,0 +1,8 @@
+[promise-rejection-events.html]
+  expected: TIMEOUT
+  [delayed handling: delaying handling rejected promise created from createImageBitmap will cause both events to fire]
+    expected: TIMEOUT
+
+  [unhandledrejection: from createImageBitmap which is UA triggered]
+    expected: FAIL
+
diff --git a/tests/wpt/metadata-layout-2020/resource-timing/resource_initiator_types.html.ini b/tests/wpt/metadata-layout-2020/resource-timing/resource_initiator_types.html.ini
index c5a1226c943..8c3617e17d7 100644
--- a/tests/wpt/metadata-layout-2020/resource-timing/resource_initiator_types.html.ini
+++ b/tests/wpt/metadata-layout-2020/resource-timing/resource_initiator_types.html.ini
@@ -1,2 +1,4 @@
 [resource_initiator_types.html]
-  expected: TIMEOUT
+  [Testing resource entries]
+    expected: FAIL
+
diff --git a/tests/wpt/metadata-layout-2020/webmessaging/without-ports/018.html.ini b/tests/wpt/metadata-layout-2020/webmessaging/with-ports/018.html.ini
similarity index 100%
rename from tests/wpt/metadata-layout-2020/webmessaging/without-ports/018.html.ini
rename to tests/wpt/metadata-layout-2020/webmessaging/with-ports/018.html.ini
diff --git a/tests/wpt/metadata-layout-2020/webmessaging/without-ports/017.html.ini b/tests/wpt/metadata-layout-2020/webmessaging/without-ports/017.html.ini
deleted file mode 100644
index 064cf47545b..00000000000
--- a/tests/wpt/metadata-layout-2020/webmessaging/without-ports/017.html.ini
+++ /dev/null
@@ -1,5 +0,0 @@
-[017.html]
-  expected: TIMEOUT
-  [origin of the script that invoked the method, about:blank]
-    expected: TIMEOUT
-
diff --git a/tests/wpt/metadata-layout-2020/workers/constructors/Worker/Worker-constructor.html.ini b/tests/wpt/metadata-layout-2020/workers/constructors/Worker/Worker-constructor.html.ini
new file mode 100644
index 00000000000..80f9a4f15b8
--- /dev/null
+++ b/tests/wpt/metadata-layout-2020/workers/constructors/Worker/Worker-constructor.html.ini
@@ -0,0 +1,2 @@
+[Worker-constructor.html]
+  expected: ERROR
diff --git a/tests/wpt/metadata-layout-2020/workers/semantics/run-a-worker/003.html.ini b/tests/wpt/metadata-layout-2020/workers/semantics/run-a-worker/003.html.ini
index dd49aa8e457..c2c57aec558 100644
--- a/tests/wpt/metadata-layout-2020/workers/semantics/run-a-worker/003.html.ini
+++ b/tests/wpt/metadata-layout-2020/workers/semantics/run-a-worker/003.html.ini
@@ -1,5 +1,4 @@
 [003.html]
-  expected: ERROR
   [shared]
     expected: FAIL
 
diff --git a/tests/wpt/metadata/MANIFEST.json b/tests/wpt/metadata/MANIFEST.json
index cdcabef6de5..ba171da9a46 100644
--- a/tests/wpt/metadata/MANIFEST.json
+++ b/tests/wpt/metadata/MANIFEST.json
@@ -162101,6 +162101,32 @@
        {}
       ]
      ],
+     "active-selection-031.html": [
+      "387bb82082f3a13cd5867aefa33b44d836d18eb8",
+      [
+       null,
+       [
+        [
+         "/css/css-pseudo/reference/active-selection-031-ref.html",
+         "=="
+        ]
+       ],
+       {}
+      ]
+     ],
+     "active-selection-045.html": [
+      "415aa60610a85327362f3a4e592168ab9fccbbe3",
+      [
+       null,
+       [
+        [
+         "/css/reference/ref-nothing-below.xht",
+         "=="
+        ]
+       ],
+       {}
+      ]
+     ],
      "active-selection-051.html": [
       "caab01e392428560331729292f99b91bd20ac20e",
       [
@@ -247708,7 +247734,7 @@
     []
    ],
    ".taskcluster.yml": [
-    "47a243a855db0ff3ed9f191170f02762e44392e1",
+    "526fc13212e9b2ac9abfb54fcdcddea63a63c80a",
     []
    ],
    ".well-known": {
@@ -305969,6 +305995,10 @@
       "active-selection-024-ref.html": [
        "e6dda1c1371b53e12f9a6601eea67ac4f5604a3b",
        []
+      ],
+      "active-selection-031-ref.html": [
+       "0e3680844f887050520d8fb9b9bd2f68a2234e85",
+       []
       ]
      },
      "selection-text-shadow-016-ref.html": [
@@ -305979,6 +306009,12 @@
       "1e068262780074b3f2acb50ae8cee69b84c72af3",
       []
      ],
+     "support": {
+      "100x100-red.png": [
+       "57bf3ddc5213d06e0975de38f330ffb7c441b268",
+       []
+      ]
+     },
      "textpath-selection-011-ref.html": [
       "d9ba940518e121eeb0e9701ccd4e36772fdfa786",
       []
@@ -345563,7 +345599,7 @@
      []
     ],
     "testdriver.js": [
-     "a8588b44f94c78f0a3c2542385bce20cfd1a64c9",
+     "4d373c9281d85e6ff37a6d0dfe4cdc2fc9c10787",
      []
     ],
     "testdriver.js.headers": [
@@ -348613,7 +348649,13 @@
     "helpers.js": [
      "c8c40646481a055cd1b7abf693e8f45cab769fba",
      []
-    ]
+    ],
+    "resources": {
+     "set-cookie.py": [
+      "019697a4a8608943e0258664138ce9a7b6ae6876",
+      []
+     ]
+    }
    },
    "streams": {
     "META.yml": [
@@ -349905,7 +349947,7 @@
        []
       ],
       "decision.py": [
-       "070ae5f1903b6dbf56f535990611c04b89690bdf",
+       "0820a6798b5b233581eb561a973cb97ff2af44e1",
        []
       ],
       "download.py": [
@@ -349922,7 +349964,7 @@
       ],
       "tasks": {
        "test.yml": [
-        "9e8e689d8163368abfb0bc7bef776581643d29d7",
+        "dd14fc71b915e90f0625dc1120aed3c86a787e53",
         []
        ]
       },
@@ -349984,7 +350026,7 @@
       []
      ],
      "Dockerfile": [
-      "6b49393bc872adc021333d6578bca41f3481ebc1",
+      "d8b64c2585f9998ecec4db2ca9adb97f650167b1",
       []
      ],
      "README.md": [
@@ -355687,7 +355729,7 @@
      }
     },
     "tox.ini": [
-     "45358c081efbb00d528d6d176b93d28dd081b8cb",
+     "1a94ec340216417584bc54bf3527d90920993789",
      []
     ],
     "wave": {
@@ -356306,7 +356348,7 @@
       []
      ],
      "browser.py": [
-      "cb5974078a8022d30402a5dac8137470e8fd1ecc",
+      "85b7b63c21972614208bda68979fd8b974535e97",
       []
      ],
      "commands.json": [
@@ -356318,7 +356360,7 @@
       []
      ],
      "install.py": [
-      "1fe091879b5ca04c16e9c965380b97025ec74521",
+      "81770225428d4605b142e18914ce142f7724b1cd",
       []
      ],
      "mach-emulator.manifest": [
@@ -356342,7 +356384,7 @@
       []
      ],
      "run.py": [
-      "32f903ce9bd64474aa387ac03a7bcb36d47bb8ae",
+      "79329a5dab4472d73fefeaf9b0d48057dc40eba1",
       []
      ],
      "testfiles.py": [
@@ -356375,12 +356417,12 @@
        []
       ],
       "test_wpt.py": [
-       "f897b688ad6f682be9d769da98579c788505c09a",
+       "d2d0b541a3796528929522ef62c2e80cb7e8735c",
        []
       ]
      },
      "tox.ini": [
-      "8e3e26e135b4d376a492aea5adbd242797b03fe0",
+      "7e6eb8e42a4c7b248988ef1984a0583961e08105",
       []
      ],
      "update.py": [
@@ -356388,7 +356430,7 @@
       []
      ],
      "utils.py": [
-      "18551481ab8cae42a6707156922619df3fa59b48",
+      "6608af754b2adaf77610552f0db4ee67e4b4e621",
       []
      ],
      "virtualenv.py": [
@@ -356634,7 +356676,7 @@
       }
      },
      "tox.ini": [
-      "c544da7a95d2a982cab8b68af537440b71fa096b",
+      "798f64a3e422e4da0b4e4b6fe15d686b20af572e",
       []
      ],
      "wptrunner": {
@@ -485259,7 +485301,7 @@
      ]
     ],
     "payment-request-hasenrolledinstrument-method.tentative.https.html": [
-     "c55312ce33b0da2fcd1d1619b6d7ff8c614a4f6b",
+     "4f6b7e9239b67e4317c325af651ab685f0c63c44",
      [
       null,
       {
@@ -485324,7 +485366,7 @@
      ]
     ],
     "payment-request-show-method.https.html": [
-     "dcf78ef4281c4256ecb4141b3f93d15a947805a3",
+     "20d5bab0d14b79fb3dcf3e82e08dc495d038a33d",
      [
       null,
       {
@@ -504577,6 +504619,15 @@
       "storage-access-api/sandboxAttribute.window.html",
       {}
      ]
+    ],
+    "storageAccess.testdriver.sub.html": [
+     "59f925f4bf503ce1cdacbe9cf17b9c10406790e4",
+     [
+      null,
+      {
+       "testdriver": true
+      }
+     ]
     ]
    },
    "streams": {
@@ -505592,7 +505643,7 @@
       ]
      ],
      "then-interception.any.js": [
-      "848bb5affd87080077c2729d91943e283f3e0c8e",
+      "9f772ea5841d8f35487e7fa978bdd187b89896cd",
       [
        null,
        {
@@ -507699,7 +507750,7 @@
       ]
      ],
      "patched-global.any.js": [
-      "bf353bc241ffab12c558912851940785bcdf62f2",
+      "416edf815c3867511ee16057624307c3e9a3fa5c",
       [
        null,
        {
diff --git a/tests/wpt/metadata/css/CSS2/floats/hit-test-floats-003.html.ini b/tests/wpt/metadata/css/CSS2/floats/hit-test-floats-003.html.ini
deleted file mode 100644
index f29da48a2a0..00000000000
--- a/tests/wpt/metadata/css/CSS2/floats/hit-test-floats-003.html.ini
+++ /dev/null
@@ -1,4 +0,0 @@
-[hit-test-floats-003.html]
-  [Miss float below something else]
-    expected: FAIL
-
diff --git a/tests/wpt/metadata/css/CSS2/floats/hit-test-floats-004.html.ini b/tests/wpt/metadata/css/CSS2/floats/hit-test-floats-004.html.ini
deleted file mode 100644
index 4bfb0c2053a..00000000000
--- a/tests/wpt/metadata/css/CSS2/floats/hit-test-floats-004.html.ini
+++ /dev/null
@@ -1,4 +0,0 @@
-[hit-test-floats-004.html]
-  [Miss float below something else]
-    expected: FAIL
-
diff --git a/tests/wpt/metadata/css/CSS2/floats/hit-test-floats-005.html.ini b/tests/wpt/metadata/css/CSS2/floats/hit-test-floats-005.html.ini
new file mode 100644
index 00000000000..baa9f1a7541
--- /dev/null
+++ b/tests/wpt/metadata/css/CSS2/floats/hit-test-floats-005.html.ini
@@ -0,0 +1,4 @@
+[hit-test-floats-005.html]
+  [Miss clipped float]
+    expected: FAIL
+
diff --git a/tests/wpt/metadata/css/CSS2/linebox/inline-negative-margin-001.html.ini b/tests/wpt/metadata/css/CSS2/linebox/inline-negative-margin-001.html.ini
index 076c791cd3d..94a3570d26b 100644
--- a/tests/wpt/metadata/css/CSS2/linebox/inline-negative-margin-001.html.ini
+++ b/tests/wpt/metadata/css/CSS2/linebox/inline-negative-margin-001.html.ini
@@ -8,9 +8,6 @@
   [[data-expected-height\] 3]
     expected: FAIL
 
-  [[data-expected-height\] 1]
-    expected: FAIL
-
-  [[data-expected-height\] 2]
+  [[data-expected-height\] 4]
     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/cssom-view/CaretPosition-001.html.ini b/tests/wpt/metadata/css/cssom-view/CaretPosition-001.html.ini
new file mode 100644
index 00000000000..4c79907309b
--- /dev/null
+++ b/tests/wpt/metadata/css/cssom-view/CaretPosition-001.html.ini
@@ -0,0 +1,4 @@
+[CaretPosition-001.html]
+  [Element at (400, 100)]
+    expected: FAIL
+
diff --git a/tests/wpt/metadata/css/cssom-view/MediaQueryList-addListener-removeListener.html.ini b/tests/wpt/metadata/css/cssom-view/MediaQueryList-addListener-removeListener.html.ini
index 628b1fab770..c884dc82eab 100644
--- a/tests/wpt/metadata/css/cssom-view/MediaQueryList-addListener-removeListener.html.ini
+++ b/tests/wpt/metadata/css/cssom-view/MediaQueryList-addListener-removeListener.html.ini
@@ -2,3 +2,6 @@
   [listeners are called when <iframe> is resized]
     expected: FAIL
 
+  [listeners are called correct number of times]
+    expected: FAIL
+
diff --git a/tests/wpt/metadata/css/cssom-view/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/elementsFromPoint-iframes.html.ini b/tests/wpt/metadata/css/cssom-view/elementsFromPoint-iframes.html.ini
index 171592fc08f..6ef8bb1049f 100644
--- a/tests/wpt/metadata/css/cssom-view/elementsFromPoint-iframes.html.ini
+++ b/tests/wpt/metadata/css/cssom-view/elementsFromPoint-iframes.html.ini
@@ -2,3 +2,6 @@
   [elementsFromPoint on the root document for points in iframe elements]
     expected: FAIL
 
+  [elementsFromPoint on inner documents]
+    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 752f9e8a824..956ba66f01f 100644
--- a/tests/wpt/metadata/fetch/content-type/response.window.js.ini
+++ b/tests/wpt/metadata/fetch/content-type/response.window.js.ini
@@ -315,15 +315,6 @@
   [<iframe>: separate response Content-Type: text/html */*]
     expected: FAIL
 
-  [<iframe>: separate response Content-Type: 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>: combined response Content-Type: text/html */*;charset=gbk]
     expected: FAIL
 
@@ -336,6 +327,6 @@
   [<iframe>: separate response Content-Type: text/html;" \\" text/plain]
     expected: FAIL
 
-  [<iframe>: combined response Content-Type: text/html;x=" text/plain]
+  [<iframe>: combined response Content-Type: text/html;" \\" text/plain]
     expected: FAIL
 
diff --git a/tests/wpt/metadata/fetch/content-type/script.window.js.ini b/tests/wpt/metadata/fetch/content-type/script.window.js.ini
index d2df9b78483..e67f0406fc3 100644
--- a/tests/wpt/metadata/fetch/content-type/script.window.js.ini
+++ b/tests/wpt/metadata/fetch/content-type/script.window.js.ini
@@ -53,6 +53,3 @@
   [combined text/javascript ]
     expected: FAIL
 
-  [separate text/javascript x/x]
-    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 30e1b851fd4..c7ffe03c4ae 100644
--- a/tests/wpt/metadata/fetch/nosniff/parsing-nosniff.window.js.ini
+++ b/tests/wpt/metadata/fetch/nosniff/parsing-nosniff.window.js.ini
@@ -11,3 +11,9 @@
   [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%22nosniFF%22]
+    expected: FAIL
+
+  [X-Content-Type-Options%3A%20%40%23%24%23%25%25%26%5E%26%5E*()()11!%2Cnosniff]
+    expected: FAIL
+
diff --git a/tests/wpt/metadata/html/browsers/history/the-history-interface/traverse_the_history_1.html.ini b/tests/wpt/metadata/html/browsers/history/the-history-interface/traverse_the_history_1.html.ini
deleted file mode 100644
index 87b07c3e670..00000000000
--- a/tests/wpt/metadata/html/browsers/history/the-history-interface/traverse_the_history_1.html.ini
+++ /dev/null
@@ -1,4 +0,0 @@
-[traverse_the_history_1.html]
-  [Multiple history traversals from the same task]
-    expected: FAIL
-
diff --git a/tests/wpt/metadata/html/browsers/history/the-history-interface/traverse_the_history_2.html.ini b/tests/wpt/metadata/html/browsers/history/the-history-interface/traverse_the_history_2.html.ini
new file mode 100644
index 00000000000..75d75b4cda2
--- /dev/null
+++ b/tests/wpt/metadata/html/browsers/history/the-history-interface/traverse_the_history_2.html.ini
@@ -0,0 +1,4 @@
+[traverse_the_history_2.html]
+  [Multiple history traversals, last would be aborted]
+    expected: FAIL
+
diff --git a/tests/wpt/metadata/html/browsers/origin/cross-origin-objects/cross-origin-objects-on-new-window.html.ini b/tests/wpt/metadata/html/browsers/origin/cross-origin-objects/cross-origin-objects-on-new-window.html.ini
deleted file mode 100644
index 735a9a75a2a..00000000000
--- a/tests/wpt/metadata/html/browsers/origin/cross-origin-objects/cross-origin-objects-on-new-window.html.ini
+++ /dev/null
@@ -1,2 +0,0 @@
-[cross-origin-objects-on-new-window.html]
-  expected: TIMEOUT
diff --git a/tests/wpt/metadata/html/browsers/windows/embedded-opener-remove-frame.html.ini b/tests/wpt/metadata/html/browsers/windows/embedded-opener-remove-frame.html.ini
index c757b400205..442db3cb549 100644
--- a/tests/wpt/metadata/html/browsers/windows/embedded-opener-remove-frame.html.ini
+++ b/tests/wpt/metadata/html/browsers/windows/embedded-opener-remove-frame.html.ini
@@ -1,5 +1,4 @@
 [embedded-opener-remove-frame.html]
-  expected: CRASH
   [opener and "removed" embedded documents]
     expected: FAIL
 
@@ -7,5 +6,5 @@
     expected: FAIL
 
   [opener of discarded auxiliary browsing context]
-    expected: TIMEOUT
+    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 6b68e9094e4..44dc9ffabc4 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
@@ -1,16 +1,20 @@
 [supported-elements.html]
+  expected: TIMEOUT
   [Contenteditable element should support autofocus]
-    expected: FAIL
+    expected: TIMEOUT
 
   [Element with tabindex should support autofocus]
-    expected: FAIL
+    expected: NOTRUN
 
   [Host element with delegatesFocus including no focusable descendants should be skipped]
-    expected: FAIL
+    expected: NOTRUN
 
   [Area element should support autofocus]
-    expected: FAIL
+    expected: NOTRUN
 
   [Host element with delegatesFocus should support autofocus]
-    expected: FAIL
+    expected: NOTRUN
+
+  [Non-HTMLElement should not support autofocus]
+    expected: NOTRUN
 
diff --git a/tests/wpt/metadata/html/semantics/embedded-content/the-iframe-element/iframe_sandbox_popups_escaping-2.html.ini b/tests/wpt/metadata/html/semantics/embedded-content/the-iframe-element/iframe_sandbox_popups_escaping-2.html.ini
index e63fe7c263e..c6f45be1eb2 100644
--- a/tests/wpt/metadata/html/semantics/embedded-content/the-iframe-element/iframe_sandbox_popups_escaping-2.html.ini
+++ b/tests/wpt/metadata/html/semantics/embedded-content/the-iframe-element/iframe_sandbox_popups_escaping-2.html.ini
@@ -1,5 +1,5 @@
 [iframe_sandbox_popups_escaping-2.html]
-  expected: CRASH
+  expected: TIMEOUT
   [Check that popups from a sandboxed iframe escape the sandbox if\n       allow-popups-to-escape-sandbox is used]
     expected: TIMEOUT
 
diff --git a/tests/wpt/metadata/html/semantics/embedded-content/the-iframe-element/iframe_sandbox_popups_escaping-3.html.ini b/tests/wpt/metadata/html/semantics/embedded-content/the-iframe-element/iframe_sandbox_popups_escaping-3.html.ini
index 5f60c78e73c..f6a7aca3306 100644
--- a/tests/wpt/metadata/html/semantics/embedded-content/the-iframe-element/iframe_sandbox_popups_escaping-3.html.ini
+++ b/tests/wpt/metadata/html/semantics/embedded-content/the-iframe-element/iframe_sandbox_popups_escaping-3.html.ini
@@ -1,6 +1,5 @@
 [iframe_sandbox_popups_escaping-3.html]
   type: testharness
-  expected: TIMEOUT
   [Check that popups from a sandboxed iframe escape the sandbox if\n       allow-popups-to-escape-sandbox is used]
-    expected: TIMEOUT
+    expected: FAIL
 
diff --git a/tests/wpt/metadata/html/semantics/embedded-content/the-iframe-element/iframe_sandbox_popups_nonescaping-2.html.ini b/tests/wpt/metadata/html/semantics/embedded-content/the-iframe-element/iframe_sandbox_popups_nonescaping-2.html.ini
index d43f38b40cd..45d8be1c898 100644
--- a/tests/wpt/metadata/html/semantics/embedded-content/the-iframe-element/iframe_sandbox_popups_nonescaping-2.html.ini
+++ b/tests/wpt/metadata/html/semantics/embedded-content/the-iframe-element/iframe_sandbox_popups_nonescaping-2.html.ini
@@ -1,6 +1,6 @@
 [iframe_sandbox_popups_nonescaping-2.html]
   type: testharness
-  expected: TIMEOUT
+  expected: CRASH
   [Check that popups from a sandboxed iframe do not escape the sandbox]
     expected: NOTRUN
 
diff --git a/tests/wpt/metadata/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 2568040e6e5..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: CRASH
   [Check that popups from a sandboxed iframe do not escape the sandbox]
     expected: FAIL
 
diff --git a/tests/wpt/metadata/html/semantics/links/links-created-by-a-and-area-elements/htmlanchorelement_noopener.html.ini b/tests/wpt/metadata/html/semantics/links/links-created-by-a-and-area-elements/htmlanchorelement_noopener.html.ini
index b3120da1666..e3c28e7d996 100644
--- a/tests/wpt/metadata/html/semantics/links/links-created-by-a-and-area-elements/htmlanchorelement_noopener.html.ini
+++ b/tests/wpt/metadata/html/semantics/links/links-created-by-a-and-area-elements/htmlanchorelement_noopener.html.ini
@@ -9,3 +9,9 @@
   [Check that rel=noopener with target=_top does a normal load]
     expected: FAIL
 
+  [Check that rel=noopener with target=_self does a normal load]
+    expected: FAIL
+
+  [Check that rel=noopener with target=_parent does a normal load]
+    expected: FAIL
+
diff --git a/tests/wpt/metadata/html/webappapis/dynamic-markup-insertion/document-write/module-static-import-delayed.html.ini b/tests/wpt/metadata/html/webappapis/dynamic-markup-insertion/document-write/module-static-import-delayed.html.ini
deleted file mode 100644
index fca4d908c89..00000000000
--- a/tests/wpt/metadata/html/webappapis/dynamic-markup-insertion/document-write/module-static-import-delayed.html.ini
+++ /dev/null
@@ -1,4 +0,0 @@
-[module-static-import-delayed.html]
-  [document.write in an imported module]
-    expected: FAIL
-
diff --git a/tests/wpt/metadata/html/webappapis/dynamic-markup-insertion/opening-the-input-stream/ignore-opens-during-unload.window.js.ini b/tests/wpt/metadata/html/webappapis/dynamic-markup-insertion/opening-the-input-stream/ignore-opens-during-unload.window.js.ini
index 69bd952d756..910c88d3e81 100644
--- a/tests/wpt/metadata/html/webappapis/dynamic-markup-insertion/opening-the-input-stream/ignore-opens-during-unload.window.js.ini
+++ b/tests/wpt/metadata/html/webappapis/dynamic-markup-insertion/opening-the-input-stream/ignore-opens-during-unload.window.js.ini
@@ -1,5 +1,5 @@
 [ignore-opens-during-unload.window.html]
-  expected: TIMEOUT
+  expected: CRASH
   [ignore-opens-during-unload]
     expected: FAIL
 
diff --git a/tests/wpt/metadata/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 5ddb9bfeff6..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
@@ -1,10 +1,9 @@
 [promise-job-entry.html]
-  expected: TIMEOUT
   [Fulfillment handler on fulfilled promise]
     expected: FAIL
 
   [Rejection handler on pending-then-rejected promise]
-    expected: TIMEOUT
+    expected: FAIL
 
   [Sanity check: this all works as expected with no promises involved]
     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/html/webappapis/scripting/processing-model-2/unhandled-promise-rejections/promise-rejection-events.html.ini b/tests/wpt/metadata/html/webappapis/scripting/processing-model-2/unhandled-promise-rejections/promise-rejection-events.html.ini
index 16614b18649..d65177c2a5b 100644
--- a/tests/wpt/metadata/html/webappapis/scripting/processing-model-2/unhandled-promise-rejections/promise-rejection-events.html.ini
+++ b/tests/wpt/metadata/html/webappapis/scripting/processing-model-2/unhandled-promise-rejections/promise-rejection-events.html.ini
@@ -1,6 +1,7 @@
 [promise-rejection-events.html]
+  expected: TIMEOUT
   [delayed handling: delaying handling rejected promise created from createImageBitmap will cause both events to fire]
-    expected: FAIL
+    expected: TIMEOUT
 
   [unhandledrejection: from createImageBitmap which is UA triggered]
     expected: FAIL
diff --git a/tests/wpt/metadata/resource-timing/resource_initiator_types.html.ini b/tests/wpt/metadata/resource-timing/resource_initiator_types.html.ini
index 85888a24ecc..7429e30d764 100644
--- a/tests/wpt/metadata/resource-timing/resource_initiator_types.html.ini
+++ b/tests/wpt/metadata/resource-timing/resource_initiator_types.html.ini
@@ -1,5 +1,4 @@
 [resource_initiator_types.html]
-  expected: TIMEOUT
   [http://web-platform.test:8000/resource-timing/resources/all_resource_types.htm is not expected to be in the Resource Timing buffer]
     expected: FAIL
 
diff --git a/tests/wpt/metadata/webmessaging/without-ports/018.html.ini b/tests/wpt/metadata/webmessaging/with-ports/018.html.ini
similarity index 100%
rename from tests/wpt/metadata/webmessaging/without-ports/018.html.ini
rename to tests/wpt/metadata/webmessaging/with-ports/018.html.ini
diff --git a/tests/wpt/metadata/webmessaging/without-ports/017.html.ini b/tests/wpt/metadata/webmessaging/without-ports/017.html.ini
deleted file mode 100644
index 064cf47545b..00000000000
--- a/tests/wpt/metadata/webmessaging/without-ports/017.html.ini
+++ /dev/null
@@ -1,5 +0,0 @@
-[017.html]
-  expected: TIMEOUT
-  [origin of the script that invoked the method, about:blank]
-    expected: TIMEOUT
-
diff --git a/tests/wpt/metadata/workers/constructors/Worker/Worker-constructor.html.ini b/tests/wpt/metadata/workers/constructors/Worker/Worker-constructor.html.ini
new file mode 100644
index 00000000000..80f9a4f15b8
--- /dev/null
+++ b/tests/wpt/metadata/workers/constructors/Worker/Worker-constructor.html.ini
@@ -0,0 +1,2 @@
+[Worker-constructor.html]
+  expected: ERROR
diff --git a/tests/wpt/metadata/workers/semantics/run-a-worker/003.html.ini b/tests/wpt/metadata/workers/semantics/run-a-worker/003.html.ini
index 49f489d2a1c..d6e39444229 100644
--- a/tests/wpt/metadata/workers/semantics/run-a-worker/003.html.ini
+++ b/tests/wpt/metadata/workers/semantics/run-a-worker/003.html.ini
@@ -1,6 +1,5 @@
 [003.html]
   type: testharness
-  expected: ERROR
   [shared]
     expected: FAIL
 
diff --git a/tests/wpt/web-platform-tests/.taskcluster.yml b/tests/wpt/web-platform-tests/.taskcluster.yml
index 47a243a855d..526fc13212e 100644
--- a/tests/wpt/web-platform-tests/.taskcluster.yml
+++ b/tests/wpt/web-platform-tests/.taskcluster.yml
@@ -57,7 +57,7 @@ tasks:
             owner: ${owner}
             source: ${event.repository.clone_url}
           payload:
-            image: webplatformtests/wpt:0.42
+            image: webplatformtests/wpt:0.46
             maxRunTime: 7200
             artifacts:
               public/results:
diff --git a/tests/wpt/web-platform-tests/css/css-pseudo/active-selection-031.html b/tests/wpt/web-platform-tests/css/css-pseudo/active-selection-031.html
new file mode 100644
index 00000000000..387bb82082f
--- /dev/null
+++ b/tests/wpt/web-platform-tests/css/css-pseudo/active-selection-031.html
@@ -0,0 +1,86 @@
+<!DOCTYPE html>
+
+  <meta charset="UTF-8">
+
+  <title>CSS Pseudo-Elements Test: active selection and vertical writing-modes</title>
+
+  <link rel="author" title="Gérard Talbot" href="http://www.gtalbot.org/BrowserBugsSection/css21testsuite/">
+  <link rel="help" href="https://www.w3.org/TR/css-pseudo-4/#highlight-styling">
+  <link rel="match" href="reference/active-selection-031-ref.html">
+
+  <meta content="" name="flags">
+
+  <style>
+  div > div
+    {
+      color: red;
+      float: left;
+      font-size: 48px;
+      margin-left: 16px;
+    }
+
+  div.vrl
+    {
+      writing-mode: vertical-rl;
+    }
+
+  div.vlr
+    {
+      writing-mode: vertical-lr;
+    }
+
+  div.mixed
+    {
+      text-orientation: mixed;
+    }
+
+  div.sideways
+    {
+      text-orientation: sideways;
+    }
+
+  div.upright
+    {
+      text-orientation: upright;
+    }
+
+  div::selection
+    {
+      background-color: yellow;
+      color: green;
+    }
+  </style>
+
+  <script>
+  function startTest()
+  {
+    var targetRange = document.createRange();
+    /* We first create an empty range */
+
+    targetRange.selectNodeContents(document.getElementById("test"));
+    /* Then we set the range boundaries to the contents of div#test */
+
+    window.getSelection().addRange(targetRange);
+    /* Finally, we now add such range of content into a selection */
+  }
+  </script>
+
+  <body onload="startTest();">
+
+  <p>Test passes if each glyph of the 6 "Selected Text" is green and if there is <strong>no red</strong>.
+
+  <div id="test">
+
+    <div class="vrl mixed">Selected Text</div>
+
+    <div class="vrl sideways">Selected Text</div>
+
+    <div class="vrl upright">Selected Text</div>
+
+    <div class="vlr mixed">Selected Text</div>
+
+    <div class="vlr sideways">Selected Text</div>
+
+    <div class="vlr upright">Selected Text</div>
+
+  </div>
diff --git a/tests/wpt/web-platform-tests/css/css-pseudo/active-selection-045.html b/tests/wpt/web-platform-tests/css/css-pseudo/active-selection-045.html
new file mode 100644
index 00000000000..415aa60610a
--- /dev/null
+++ b/tests/wpt/web-platform-tests/css/css-pseudo/active-selection-045.html
@@ -0,0 +1,65 @@
+<!DOCTYPE html>
+
+<html class="reftest-wait">
+
+  <meta charset="UTF-8">
+
+  <title>CSS Pseudo-Elements Test: active selection and image</title>
+
+  <link rel="author" title="Gérard Talbot" href="http://www.gtalbot.org/BrowserBugsSection/css21testsuite/">
+  <link rel="help" href="https://www.w3.org/TR/css-pseudo-4/#highlight-painting">
+  <link rel="match" href="../reference/ref-nothing-below.xht">
+
+  <meta content="" name="flags">
+  <meta name="assert" content="This test checks that the associated overlay for image must not cover (or leak) outside the image's content box.">
+
+  <style>
+  /*
+  Chromium 80+ highlights the
+  top of line box minus
+  content box and the bottom
+  of line box minus content
+  box.
+  Firefox 72+ consistently highlights
+  only the image content box itself.
+  */
+
+  div
+    {
+      font-size: 300px;
+    }
+
+  img::selection
+    {
+      background-color: red;
+    }
+
+  span#masking
+    {
+      background-color: white;
+      display: inline-block;
+      height: 100px;
+      position: relative;
+      right: 100px;
+      width: 100px;
+    }
+  </style>
+
+  <script>
+  function startTest()
+  {
+  var targetRange = document.createRange();
+  /* We first create an empty range */
+  targetRange.selectNodeContents(document.getElementById("test"));
+  /* Then we set the range boundaries to the children of div#test */
+  window.getSelection().addRange(targetRange);
+  /* Finally, we now select such range of content */
+  document.documentElement.className = "";
+  }
+  </script>
+
+  <body onload="startTest();">
+
+  <p>Test passes if there is nothing below.
+
+  <div id="test"><img src="support/100x100-red.png" alt="Image download support must be enabled"><span id="masking"></span></div>
diff --git a/tests/wpt/web-platform-tests/css/css-pseudo/reference/active-selection-031-ref.html b/tests/wpt/web-platform-tests/css/css-pseudo/reference/active-selection-031-ref.html
new file mode 100644
index 00000000000..0e3680844f8
--- /dev/null
+++ b/tests/wpt/web-platform-tests/css/css-pseudo/reference/active-selection-031-ref.html
@@ -0,0 +1,57 @@
+<!DOCTYPE html>
+
+  <meta charset="UTF-8">
+
+  <title>CSS Reftest Reference</title>
+
+  <link rel="author" title="Gérard Talbot" href="http://www.gtalbot.org/BrowserBugsSection/css21testsuite/">
+
+  <style>
+  div
+    {
+      background-color: yellow;
+      color: green;
+      float: left;
+      font-size: 48px;
+      margin-left: 16px;
+    }
+
+  div.vrl
+    {
+      writing-mode: vertical-rl;
+    }
+
+  div.vlr
+    {
+      writing-mode: vertical-lr;
+    }
+
+  div.mixed
+    {
+      text-orientation: mixed;
+    }
+
+  div.sideways
+    {
+      text-orientation: sideways;
+    }
+
+  div.upright
+    {
+      text-orientation: upright;
+    }
+  </style>
+
+  <p>Test passes if each glyph of the 6 "Selected Text" is green and if there is <strong>no red</strong>.
+
+  <div class="vrl mixed">Selected Text</div>
+
+  <div class="vrl sideways">Selected Text</div>
+
+  <div class="vrl upright">Selected Text</div>
+
+  <div class="vlr mixed">Selected Text</div>
+
+  <div class="vlr sideways">Selected Text</div>
+
+  <div class="vlr upright">Selected Text</div>
diff --git a/tests/wpt/web-platform-tests/css/css-pseudo/support/100x100-red.png b/tests/wpt/web-platform-tests/css/css-pseudo/support/100x100-red.png
new file mode 100644
index 00000000000..57bf3ddc521
Binary files /dev/null and b/tests/wpt/web-platform-tests/css/css-pseudo/support/100x100-red.png differ
diff --git a/tests/wpt/web-platform-tests/payment-request/payment-request-hasenrolledinstrument-method.tentative.https.html b/tests/wpt/web-platform-tests/payment-request/payment-request-hasenrolledinstrument-method.tentative.https.html
index c55312ce33b..4f6b7e9239b 100644
--- a/tests/wpt/web-platform-tests/payment-request/payment-request-hasenrolledinstrument-method.tentative.https.html
+++ b/tests/wpt/web-platform-tests/payment-request/payment-request-hasenrolledinstrument-method.tentative.https.html
@@ -8,6 +8,9 @@
 <script src='/resources/testdriver-vendor.js'></script>
 <script>
 "use strict";
+
+setup({ allow_uncaught_exception: true });
+
 const unsupportedMethods = [
   { supportedMethods: "this-is-not-supported" },
   { supportedMethods: "https://not.supported" },
diff --git a/tests/wpt/web-platform-tests/payment-request/payment-request-show-method.https.html b/tests/wpt/web-platform-tests/payment-request/payment-request-show-method.https.html
index dcf78ef4281..20d5bab0d14 100644
--- a/tests/wpt/web-platform-tests/payment-request/payment-request-show-method.https.html
+++ b/tests/wpt/web-platform-tests/payment-request/payment-request-show-method.https.html
@@ -8,6 +8,9 @@
 <script src="/resources/testdriver-vendor.js"></script>
 <script>
 "use strict";
+
+setup({ allow_uncaught_exception: true });
+
 const defaultMethods = Object.freeze([
   { supportedMethods: "basic-card" },
   {
diff --git a/tests/wpt/web-platform-tests/resources/testdriver.js b/tests/wpt/web-platform-tests/resources/testdriver.js
index a8588b44f94..4d373c9281d 100644
--- a/tests/wpt/web-platform-tests/resources/testdriver.js
+++ b/tests/wpt/web-platform-tests/resources/testdriver.js
@@ -355,6 +355,32 @@
         set_user_verified: function(authenticator_id, uv) {
             return window.test_driver_internal.set_user_verified(authenticator_id, uv);
         },
+
+        /**
+         * Sets the storage access rule for an origin when embedded
+         * in a third-party context.
+         *
+         * {@link https://privacycg.github.io/storage-access/#set-storage-access-command}
+         *
+         * @param {String} origin - A third-party origin to block or allow.
+         *                          May be "*" to indicate all origins.
+         * @param {String} embedding_origin - an embedding (first-party) origin
+         *                                    on which {origin}'s access should
+         *                                    be blocked or allowed.
+         *                                    May be "*" to indicate all origins.
+         * @param {String} state - The storage access setting.
+         *                         Must be either "allowed" or "blocked".
+         *
+         * @returns {Promise} Fulfilled after the storage access rule has been
+         *                    set, or rejected if setting the rule fails.
+         */
+        set_storage_access: function(origin, embedding_origin, state) {
+            if (state !== "allowed" && state !== "blocked") {
+                throw new Error("storage access status must be 'allowed' or 'blocked'");
+            }
+            const blocked = state === "blocked";
+            return window.test_driver_internal.set_storage_access(origin, embedding_origin, blocked);
+        },
     };
 
     window.test_driver_internal = {
@@ -569,5 +595,13 @@
         set_user_verified: function(authenticator_id, uv) {
             return Promise.reject(new Error("unimplemented"));
         },
+
+        /**
+         * Sets the storage access policy for a third-party origin when loaded
+         * in the current first party context
+         */
+        set_storage_access: function(origin, embedding_origin, blocked) {
+            return Promise.reject(new Error("unimplemented"));
+        },
     };
 })();
diff --git a/tests/wpt/web-platform-tests/storage-access-api/resources/set-cookie.py b/tests/wpt/web-platform-tests/storage-access-api/resources/set-cookie.py
new file mode 100644
index 00000000000..019697a4a86
--- /dev/null
+++ b/tests/wpt/web-platform-tests/storage-access-api/resources/set-cookie.py
@@ -0,0 +1,27 @@
+def main(request, response):
+  name = request.GET.first(b"name")
+  value = request.GET.first(b"value")
+  testcase = request.GET.first(b"testcase")
+  response_headers = [(b"Set-Cookie", name + b"=" + value)]
+
+  body = b"""
+  <!DOCTYPE html>
+  <meta charset="utf-8">
+  <title>Set Storage Access Subframe</title>
+  <script src="/resources/testharness.js"></script>
+
+  <script>
+    let querystring = window.location.search.substring(1).split("&");
+    const allowed = querystring.some(param => param.toLowerCase() === "allowed=true");
+
+    test(() => {
+      if (allowed) {
+        assert_equals(document.cookie, "%s=%s");
+      } else {
+        assert_equals(document.cookie, "");
+      }
+    }, "[%s] Cookie access is allowed: " + allowed);
+  </script>
+  """ % (name, value, testcase)
+
+  return (200, response_headers, body)
diff --git a/tests/wpt/web-platform-tests/storage-access-api/storageAccess.testdriver.sub.html b/tests/wpt/web-platform-tests/storage-access-api/storageAccess.testdriver.sub.html
new file mode 100644
index 00000000000..59f925f4bf5
--- /dev/null
+++ b/tests/wpt/web-platform-tests/storage-access-api/storageAccess.testdriver.sub.html
@@ -0,0 +1,31 @@
+<!DOCTYPE html>
+<head>
+  <title>TestDriver - Set Storage Access Command Tests</title>
+  <script src="/resources/testharness.js"></script>
+  <script src="/resources/testharnessreport.js"></script>
+  <script src="/resources/testdriver.js"></script>
+  <script src="/resources/testdriver-vendor.js"></script>
+  <script src="helpers.js"></script>
+</head>
+<body>
+  <script>
+    "use strict";
+
+    promise_test(async t => {
+      // Allow a third-party site embedded in this first-party site.
+      await window.test_driver.set_storage_access("http://{{domains[www]}}:{{ports[http][0]}}/", "http://{{domains[]}}:{{ports[http][0]}}/", "allowed");
+      // Block a third-party site embedded in this first-party site.
+      await window.test_driver.set_storage_access("http://{{domains[www1]}}:{{ports[http][0]}}/", "http://{{domains[]}}:{{ports[http][0]}}/", "blocked");
+      // Block a third-party site on all first-party sites.
+      await window.test_driver.set_storage_access("http://{{domains[www2]}}:{{ports[http][0]}}/", "*", "blocked");
+    }, "Set up storage access rules");
+
+    RunTestsInIFrame("http://{{domains[]}}:{{ports[http][0]}}/storage-access-api/resources/set-cookie.py?name=hello0&value=world0&allowed=true&testcase=same-site");
+
+    RunTestsInIFrame("http://{{domains[www]}}:{{ports[http][0]}}/storage-access-api/resources/set-cookie.py?name=hello&value=world&allowed=true&testcase=third-party-allowed-on-first-party-site");
+
+    RunTestsInIFrame("http://{{domains[www1]}}:{{ports[http][0]}}/storage-access-api/resources/set-cookie.py?name=hello1&value=world1&allowed=false&testcase=third-party-blocked-on-first-party-site");
+
+    RunTestsInIFrame("http://{{domains[www2]}}:{{ports[http][0]}}/storage-access-api/resources/set-cookie.py?name=hello2&value=world2&allowed=false&testcase=third-party-blocked-all");
+  </script>
+</body>
diff --git a/tests/wpt/web-platform-tests/streams/piping/then-interception.any.js b/tests/wpt/web-platform-tests/streams/piping/then-interception.any.js
index 848bb5affd8..9f772ea5841 100644
--- a/tests/wpt/web-platform-tests/streams/piping/then-interception.any.js
+++ b/tests/wpt/web-platform-tests/streams/piping/then-interception.any.js
@@ -5,7 +5,7 @@
 
 function interceptThen() {
   const intercepted = [];
-  const callCount = 0;
+  let callCount = 0;
   Object.prototype.then = function(resolver) {
     if (!this.done) {
       intercepted.push(this.value);
@@ -21,7 +21,7 @@ function interceptThen() {
   return intercepted;
 }
 
-promise_test(async () => {
+promise_test(async t => {
   const rs = new ReadableStream({
     start(controller) {
       controller.enqueue('a');
@@ -31,6 +31,9 @@ promise_test(async () => {
   const ws = recordingWritableStream();
 
   const intercepted = interceptThen();
+  t.add_cleanup(() => {
+    delete Object.prototype.then;
+  });
 
   await rs.pipeTo(ws);
   delete Object.prototype.then;
@@ -40,7 +43,7 @@ promise_test(async () => {
   assert_array_equals(ws.events, ['write', 'a', 'close'], 'written chunk should be "a"');
 }, 'piping should not be observable');
 
-promise_test(async () => {
+promise_test(async t => {
   const rs = new ReadableStream({
     start(controller) {
       controller.enqueue('a');
@@ -52,6 +55,9 @@ promise_test(async () => {
   const [ branch1, branch2 ] = rs.tee();
 
   const intercepted = interceptThen();
+  t.add_cleanup(() => {
+    delete Object.prototype.then;
+  });
 
   await branch1.pipeTo(ws);
   delete Object.prototype.then;
diff --git a/tests/wpt/web-platform-tests/streams/transform-streams/patched-global.any.js b/tests/wpt/web-platform-tests/streams/transform-streams/patched-global.any.js
index bf353bc241f..416edf815c3 100644
--- a/tests/wpt/web-platform-tests/streams/transform-streams/patched-global.any.js
+++ b/tests/wpt/web-platform-tests/streams/transform-streams/patched-global.any.js
@@ -1,19 +1,25 @@
 // META: global=window,worker,jsshell
 'use strict';
 
-// Tests which patch the global environment are kept separate to avoid interfering with other tests.
+// Tests which patch the global environment are kept separate to avoid
+// interfering with other tests.
 
-// eslint-disable-next-line no-extend-native, accessor-pairs
-Object.defineProperty(Object.prototype, 'highWaterMark', {
-  set() { throw new Error('highWaterMark setter called'); }
-});
+test(t => {
+  // eslint-disable-next-line no-extend-native, accessor-pairs
+  Object.defineProperty(Object.prototype, 'highWaterMark', {
+    set() { throw new Error('highWaterMark setter called'); }
+  });
 
-// eslint-disable-next-line no-extend-native, accessor-pairs
-Object.defineProperty(Object.prototype, 'size', {
-  set() { throw new Error('size setter called'); }
-});
+  // eslint-disable-next-line no-extend-native, accessor-pairs
+  Object.defineProperty(Object.prototype, 'size', {
+    set() { throw new Error('size setter called'); }
+  });
+
+  t.add_cleanup(() => {
+    delete Object.prototype.highWaterMark;
+    delete Object.prototype.size;
+  });
 
-test(() => {
   assert_not_equals(new TransformStream(), null, 'constructor should work');
 }, 'TransformStream constructor should not call setters for highWaterMark or size');
 
diff --git a/tests/wpt/web-platform-tests/tools/ci/tc/decision.py b/tests/wpt/web-platform-tests/tools/ci/tc/decision.py
index 070ae5f1903..0820a6798b5 100644
--- a/tests/wpt/web-platform-tests/tools/ci/tc/decision.py
+++ b/tests/wpt/web-platform-tests/tools/ci/tc/decision.py
@@ -199,7 +199,6 @@ def build_full_command(event, task):
 ~/start.sh \
   %(repo_url)s \
   %(fetch_ref)s;
-sudo add-apt-repository ppa:deadsnakes/ppa
 %(install_str)s
 cd web-platform-tests;
 ./tools/ci/run_tc.py %(options_str)s -- %(task_cmd)s;
diff --git a/tests/wpt/web-platform-tests/tools/ci/tc/tasks/test.yml b/tests/wpt/web-platform-tests/tools/ci/tc/tasks/test.yml
index 9e8e689d816..dd14fc71b91 100644
--- a/tests/wpt/web-platform-tests/tools/ci/tc/tasks/test.yml
+++ b/tests/wpt/web-platform-tests/tools/ci/tc/tasks/test.yml
@@ -4,7 +4,7 @@ components:
     workerType: ci
     schedulerId: taskcluster-github
     deadline: "24 hours"
-    image: webplatformtests/wpt:0.42
+    image: webplatformtests/wpt:0.46
     maxRunTime: 7200
     artifacts:
       public/results:
@@ -392,6 +392,9 @@ tasks:
         - trigger-pr
         - tox-python3
       command: ./tools/ci/ci_tools_unittest.sh
+      install:
+        - python3.6
+        - python3.6-dev
       env:
         HYPOTHESIS_PROFILE: ci
       schedule-if:
@@ -444,6 +447,8 @@ tasks:
       command: ./tools/ci/ci_tools_integration_test.sh
       install:
         - libnss3-tools
+        - python3.6
+        - python3.6-dev
       options:
         oom-killer: true
         browser:
diff --git a/tests/wpt/web-platform-tests/tools/docker/Dockerfile b/tests/wpt/web-platform-tests/tools/docker/Dockerfile
index 6b49393bc87..d8b64c2585f 100644
--- a/tests/wpt/web-platform-tests/tools/docker/Dockerfile
+++ b/tests/wpt/web-platform-tests/tools/docker/Dockerfile
@@ -1,4 +1,4 @@
-FROM ubuntu:18.04
+FROM ubuntu:20.04
 
 # No interactive frontend during docker build
 ENV DEBIAN_FRONTEND=noninteractive \
@@ -10,12 +10,14 @@ RUN apt-get -qqy update \
     bridge-utils \
     bzip2 \
     ca-certificates \
+    curl \
     dbus-x11 \
     earlyoom \
     fluxbox \
     gdebi \
     git \
     gstreamer1.0-plugins-bad \
+    gstreamer1.0-gl \
     libosmesa6-dev \
     libvirt-daemon-system \
     libvirt-clients \
@@ -24,10 +26,12 @@ RUN apt-get -qqy update \
     locales \
     openjdk-8-jre-headless \
     pulseaudio \
-    python \
-    python-pip \
+    python2 \
+    python2-dev \
     python3 \
+    python3-dev \
     python3-pip \
+    software-properties-common \
     qemu-kvm \
     tzdata \
     sudo \
@@ -35,6 +39,16 @@ RUN apt-get -qqy update \
     wget \
     xvfb
 
+# python3.6 is not available by default in new versions of Ubuntu.
+RUN apt-add-repository -y ppa:deadsnakes/ppa
+
+# Ensure that scripts referencing `/usr/bin/env python` work.
+RUN apt install python-is-python2
+
+# The python-pip package no longer exists in new versions of Ubuntu.
+RUN curl https://bootstrap.pypa.io/get-pip.py --output get-pip.py
+RUN python2 get-pip.py
+
 # Installing just the deps of firefox and chrome is moderately tricky, so
 # just install the default versions of them, and some extra deps we happen
 # to know that chrome requires
diff --git a/tests/wpt/web-platform-tests/tools/tox.ini b/tests/wpt/web-platform-tests/tools/tox.ini
index 45358c081ef..1a94ec34021 100644
--- a/tests/wpt/web-platform-tests/tools/tox.ini
+++ b/tests/wpt/web-platform-tests/tools/tox.ini
@@ -7,7 +7,8 @@ skip_missing_interpreters = False
 deps =
   pytest
   pytest-cov
-  mock
+  # mock no longer supports Python 2 since v4
+  mock==3.*
   hypothesis
   requests
   taskcluster
diff --git a/tests/wpt/web-platform-tests/tools/wpt/browser.py b/tests/wpt/web-platform-tests/tools/wpt/browser.py
index cb5974078a8..85b7b63c219 100644
--- a/tests/wpt/web-platform-tests/tools/wpt/browser.py
+++ b/tests/wpt/web-platform-tests/tools/wpt/browser.py
@@ -3,7 +3,6 @@ import platform
 import re
 import shutil
 import stat
-import errno
 import subprocess
 import tempfile
 from abc import ABCMeta, abstractmethod
@@ -13,7 +12,7 @@ from distutils.spawn import find_executable
 from six.moves.urllib.parse import urlsplit
 import requests
 
-from .utils import call, get, untar, unzip
+from .utils import call, get, rmtree, untar, unzip
 
 uname = platform.uname()
 
@@ -31,15 +30,6 @@ def _get_fileversion(binary, logger=None):
         return None
 
 
-def handle_remove_readonly(func, path, exc):
-    excvalue = exc[1]
-    if func in (os.rmdir, os.remove) and excvalue.errno == errno.EACCES:
-        os.chmod(path, stat.S_IRWXU | stat.S_IRWXG | stat.S_IRWXO)  # 0777
-        func(path)
-    else:
-        raise
-
-
 def get_ext(filename):
     """Get the extension from a filename with special handling for .tar.foo"""
     name, ext = os.path.splitext(filename)
@@ -63,6 +53,18 @@ class Browser(object):
     def __init__(self, logger):
         self.logger = logger
 
+    def _get_dest(self, dest, channel):
+        if dest is None:
+            # os.getcwd() doesn't include the venv path
+            dest = os.path.join(os.getcwd(), "_venv")
+
+        dest = os.path.join(dest, "browsers", channel)
+
+        if not os.path.exists(dest):
+            os.makedirs(dest)
+
+        return dest
+
     @abstractmethod
     def download(self, dest=None, channel=None, rename=None):
         """Download a package or installer for the browser
@@ -156,18 +158,6 @@ class Firefox(Browser):
 
         return "%s%s" % (self.platform, bits)
 
-    def _get_dest(self, dest, channel):
-        if dest is None:
-            # os.getcwd() doesn't include the venv path
-            dest = os.path.join(os.getcwd(), "_venv")
-
-        dest = os.path.join(dest, "browsers", channel)
-
-        if not os.path.exists(dest):
-            os.makedirs(dest)
-
-        return dest
-
     def download(self, dest=None, channel="nightly", rename=None):
         product = {
             "nightly": "firefox-nightly-latest-ssl",
@@ -374,7 +364,7 @@ class Firefox(Browser):
         # If we don't have a recent download, grab and extract the latest one
         if not have_cache:
             if os.path.exists(dest):
-                shutil.rmtree(dest)
+                rmtree(dest)
             os.makedirs(dest)
 
             url = self.get_profile_bundle_url(version, channel)
@@ -389,7 +379,7 @@ class Firefox(Browser):
                     path = os.path.join(profiles, name)
                     shutil.move(path, dest)
             finally:
-                shutil.rmtree(extract_dir)
+                rmtree(extract_dir)
         else:
             self.logger.info("Using cached test prefs from %s" % dest)
 
@@ -534,22 +524,48 @@ class Chrome(Browser):
 
     product = "chrome"
     requirements = "requirements_chrome.txt"
+    platforms = {
+        "Linux": "Linux",
+        "Windows": "Win",
+        "Darwin": "Mac",
+    }
+
+    def __init__(self, logger):
+        super(Chrome, self).__init__(logger)
+        self._last_change = None
 
     def download(self, dest=None, channel=None, rename=None):
-        raise NotImplementedError
+        if channel != "nightly":
+            raise NotImplementedError("We can only download Chrome Nightly (Chromium ToT) for you.")
+        if dest is None:
+            dest = self._get_dest(None, channel)
+
+        filename = self._chromium_package_name() + ".zip"
+        url = self._latest_chromium_snapshot_url() + filename
+        self.logger.info("Downloading Chrome from %s" % url)
+        resp = get(url)
+        installer_path = os.path.join(dest, filename)
+        with open(installer_path, "wb") as f:
+            f.write(resp.content)
+        return installer_path
 
     def install(self, dest=None, channel=None):
-        raise NotImplementedError
+        if channel != "nightly":
+            raise NotImplementedError("We can only install Chrome Nightly (Chromium ToT) for you.")
+        dest = self._get_dest(dest, channel)
 
-    def platform_string(self):
-        platform = {
-            "Linux": "linux",
-            "Windows": "win",
-            "Darwin": "mac"
-        }.get(uname[0])
+        installer_path = self.download(dest, channel)
+        with open(installer_path, "rb") as f:
+            unzip(f, dest)
+        os.remove(installer_path)
+        return self.find_nightly_binary(dest, channel)
+
+    def _chromedriver_platform_string(self):
+        platform = self.platforms.get(uname[0])
 
         if platform is None:
             raise ValueError("Unable to construct a valid Chrome package name for current platform")
+        platform = platform.lower()
 
         if platform == "linux":
             bits = "64" if uname[4] == "x86_64" else "32"
@@ -560,12 +576,8 @@ class Chrome(Browser):
 
         return "%s%s" % (platform, bits)
 
-    def chromium_platform_string(self):
-        platform = {
-            "Linux": "Linux",
-            "Windows": "Win",
-            "Darwin": "Mac"
-        }.get(uname[0])
+    def _chromium_platform_string(self):
+        platform = self.platforms.get(uname[0])
 
         if platform is None:
             raise ValueError("Unable to construct a valid Chromium package name for current platform")
@@ -575,7 +587,26 @@ class Chrome(Browser):
 
         return platform
 
+    def _chromium_package_name(self):
+        return "chrome-%s" % self.platforms.get(uname[0]).lower()
+
+    def _latest_chromium_snapshot_url(self):
+        # Make sure we use the same revision in an invocation.
+        architecture = self._chromium_platform_string()
+        if self._last_change is None:
+            revision_url = "https://storage.googleapis.com/chromium-browser-snapshots/%s/LAST_CHANGE" % architecture
+            self._last_change = get(revision_url).text.strip()
+        return "https://storage.googleapis.com/chromium-browser-snapshots/%s/%s/" % (architecture, self._last_change)
+
+    def find_nightly_binary(self, dest, channel):
+        binary = "Chromium" if uname[0] == "Darwin" else "chrome"
+        # find_executable will add .exe on Windows automatically.
+        return find_executable(binary, os.path.join(dest, self._chromium_package_name()))
+
     def find_binary(self, venv_path=None, channel=None):
+        if channel == "nightly":
+            return self.find_nightly_binary(self._get_dest(venv_path, channel))
+
         if uname[0] == "Linux":
             name = "google-chrome"
             if channel == "stable":
@@ -613,25 +644,23 @@ class Chrome(Browser):
             except requests.RequestException:
                 return None
         return "https://chromedriver.storage.googleapis.com/%s/chromedriver_%s.zip" % (
-            latest, self.platform_string())
+            latest, self._chromedriver_platform_string())
 
     def _chromium_chromedriver_url(self, chrome_version):
-        try:
-            # Try to find the Chromium build with the same revision.
-            omaha = get("https://omahaproxy.appspot.com/deps.json?version=" + chrome_version).json()
-            revision = omaha['chromium_base_position']
-            url = "https://storage.googleapis.com/chromium-browser-snapshots/%s/%s/chromedriver_%s.zip" % (
-                self.chromium_platform_string(), revision, self.platform_string())
-            # Check the status without downloading the content (this is a streaming request).
-            get(url)
-        except requests.RequestException:
-            # Fall back to the tip-of-tree Chromium build.
-            revision_url = "https://storage.googleapis.com/chromium-browser-snapshots/%s/LAST_CHANGE" % (
-                self.chromium_platform_string())
-            revision = get(revision_url).text.strip()
-            url = "https://storage.googleapis.com/chromium-browser-snapshots/%s/%s/chromedriver_%s.zip" % (
-                self.chromium_platform_string(), revision, self.platform_string())
-        return url
+        if chrome_version:
+            try:
+                # Try to find the Chromium build with the same revision.
+                omaha = get("https://omahaproxy.appspot.com/deps.json?version=" + chrome_version).json()
+                revision = omaha['chromium_base_position']
+                url = "https://storage.googleapis.com/chromium-browser-snapshots/%s/%s/chromedriver_%s.zip" % (
+                    self._chromium_platform_string(), revision, self._chromedriver_platform_string())
+                # Check the status without downloading the content (this is a streaming request).
+                get(url)
+                return url
+            except requests.RequestException:
+                pass
+        # Fall back to the tip-of-tree Chromium build.
+        return "%schromedriver_%s.zip" % (self._latest_chromium_snapshot_url(), self._chromedriver_platform_string())
 
     def _latest_chromedriver_url(self, chrome_version):
         # Remove channel suffixes (e.g. " dev").
@@ -640,20 +669,25 @@ class Chrome(Browser):
                 self._chromium_chromedriver_url(chrome_version))
 
     def install_webdriver_by_version(self, version, dest=None):
-        assert version, "Cannot install ChromeDriver without Chrome version"
         if dest is None:
             dest = os.pwd
-        url = self._latest_chromedriver_url(version)
+        url = self._latest_chromedriver_url(version) if version \
+            else self._chromium_chromedriver_url(None)
         self.logger.info("Downloading ChromeDriver from %s" % url)
         unzip(get(url).raw, dest)
         chromedriver_dir = os.path.join(
-            dest, 'chromedriver_%s' % self.platform_string())
-        if os.path.isfile(os.path.join(chromedriver_dir, "chromedriver")):
-            shutil.move(os.path.join(chromedriver_dir, "chromedriver"), dest)
-            shutil.rmtree(chromedriver_dir)
+            dest, 'chromedriver_%s' % self._chromedriver_platform_string())
+        unzipped_path = find_executable("chromedriver", chromedriver_dir)
+        assert unzipped_path is not None
+        shutil.move(unzipped_path, dest)
+        rmtree(chromedriver_dir)
         return find_executable("chromedriver", dest)
 
     def install_webdriver(self, dest=None, channel=None, browser_binary=None):
+        if channel == "nightly":
+            # The "nightly" channel is not an official channel, so we simply download ToT.
+            return self.install_webdriver_by_version(None, dest)
+
         if browser_binary is None:
             browser_binary = self.find_binary(channel)
         return self.install_webdriver_by_version(
@@ -878,7 +912,7 @@ class Opera(Browser):
 
         operadriver_dir = os.path.join(dest, "operadriver_%s" % self.platform_string())
         shutil.move(os.path.join(operadriver_dir, "operadriver"), dest)
-        shutil.rmtree(operadriver_dir)
+        rmtree(operadriver_dir)
 
         path = find_executable("operadriver")
         st = os.stat(path)
@@ -975,7 +1009,7 @@ class EdgeChromium(Browser):
         driver_notes_path = os.path.join(dest, "Driver_notes")
         if os.path.isdir(driver_notes_path):
             print("Delete %s folder" % driver_notes_path)
-            shutil.rmtree(driver_notes_path, ignore_errors=False, onerror=handle_remove_readonly)
+            rmtree(driver_notes_path)
 
         self.logger.info("Downloading MSEdgeDriver from %s" % url)
         unzip(get(url).raw, dest)
diff --git a/tests/wpt/web-platform-tests/tools/wpt/install.py b/tests/wpt/web-platform-tests/tools/wpt/install.py
index 1fe091879b5..81770225428 100644
--- a/tests/wpt/web-platform-tests/tools/wpt/install.py
+++ b/tests/wpt/web-platform-tests/tools/wpt/install.py
@@ -3,7 +3,7 @@ from . import browser
 
 latest_channels = {
     'firefox': 'nightly',
-    'chrome': 'dev',
+    'chrome': 'nightly',
     'chrome_android': 'dev',
     'edgechromium': 'dev',
     'safari': 'preview',
@@ -14,11 +14,11 @@ channel_by_name = {
     'stable': 'stable',
     'release': 'stable',
     'beta': 'beta',
+    'dev': 'dev',
+    'canary': 'canary',
     'nightly': latest_channels,
-    'dev': latest_channels,
     'preview': latest_channels,
     'experimental': latest_channels,
-    'canary': 'canary',
 }
 
 channel_args = argparse.ArgumentParser(add_help=False)
diff --git a/tests/wpt/web-platform-tests/tools/wpt/run.py b/tests/wpt/web-platform-tests/tools/wpt/run.py
index 32f903ce9bd..79329a5dab4 100644
--- a/tests/wpt/web-platform-tests/tools/wpt/run.py
+++ b/tests/wpt/web-platform-tests/tools/wpt/run.py
@@ -343,8 +343,8 @@ class Chrome(BrowserSetup):
                 kwargs["webdriver_binary"] = webdriver_binary
             else:
                 raise WptrunError("Unable to locate or install chromedriver binary")
-        if browser_channel in ("dev", "canary"):
-            logger.info("Automatically turning on experimental features for Chrome Dev/Canary")
+        if browser_channel in ("dev", "canary", "nightly"):
+            logger.info("Automatically turning on experimental features for Chrome Dev/Canary or Chromium trunk")
             kwargs["binary_args"].append("--enable-experimental-web-platform-features")
             # HACK(Hexcles): work around https://github.com/web-platform-tests/wpt/issues/16448
             kwargs["webdriver_args"].append("--disable-build-check")
diff --git a/tests/wpt/web-platform-tests/tools/wpt/tests/test_wpt.py b/tests/wpt/web-platform-tests/tools/wpt/tests/test_wpt.py
index f897b688ad6..d2d0b541a37 100644
--- a/tests/wpt/web-platform-tests/tools/wpt/tests/test_wpt.py
+++ b/tests/wpt/web-platform-tests/tools/wpt/tests/test_wpt.py
@@ -16,7 +16,7 @@ except ImportError:
 
 import pytest
 
-from tools.wpt import wpt
+from tools.wpt import utils, wpt
 
 
 here = os.path.abspath(os.path.dirname(__file__))
@@ -61,7 +61,7 @@ def manifest_dir():
                         os.path.join(path, "MANIFEST.json"))
         yield path
     finally:
-        shutil.rmtree(path)
+        utils.rmtree(path)
 
 
 @pytest.fixture
@@ -86,7 +86,7 @@ def temp_test():
 
     yield make_test
 
-    shutil.rmtree("../../.tools-tests")
+    utils.rmtree("../../.tools-tests")
 
 
 def test_missing():
@@ -185,6 +185,7 @@ def test_run_zero_tests():
                        "chrome", "/non-existent-dir/non-existent-file.html"])
     assert excinfo.value.code != 0
 
+
 @pytest.mark.slow
 @pytest.mark.remote_network
 def test_run_failing_test():
@@ -238,6 +239,25 @@ def test_run_verify_unstable(temp_test):
     assert excinfo.value.code == 0
 
 
+@pytest.mark.slow
+@pytest.mark.remote_network
+def test_install_chromium():
+    if sys.platform == "win32":
+        chromium_path = os.path.join(wpt.localpaths.repo_root, wpt.venv_dir(), "browsers", "nightly", "chrome-win")
+    elif sys.platform == "darwin":
+        chromium_path = os.path.join(wpt.localpaths.repo_root, wpt.venv_dir(), "browsers", "nightly", "chrome-mac")
+    else:
+        chromium_path = os.path.join(wpt.localpaths.repo_root, wpt.venv_dir(), "browsers", "nightly", "chrome-linux")
+
+    if os.path.exists(chromium_path):
+        utils.rmtree(chromium_path)
+    with pytest.raises(SystemExit) as excinfo:
+        wpt.main(argv=["install", "chrome", "browser", "--channel=nightly"])
+    assert excinfo.value.code == 0
+    assert os.path.exists(chromium_path)
+    utils.rmtree(chromium_path)
+
+
 @pytest.mark.slow
 @pytest.mark.remote_network
 def test_install_chromedriver():
@@ -251,7 +271,13 @@ def test_install_chromedriver():
         wpt.main(argv=["install", "chrome", "webdriver"])
     assert excinfo.value.code == 0
     assert os.path.exists(chromedriver_path)
-    os.unlink(chromedriver_path)
+    # FIXME: On Windows, this may sometimes fail (access denied), possibly
+    # because the file handler is not released immediately.
+    try:
+        os.unlink(chromedriver_path)
+    except OSError:
+        if sys.platform != "win32":
+            raise
 
 
 @pytest.mark.slow
@@ -264,12 +290,12 @@ def test_install_firefox():
     else:
         fx_path = os.path.join(wpt.localpaths.repo_root, wpt.venv_dir(), "browsers", "nightly", "firefox")
     if os.path.exists(fx_path):
-        shutil.rmtree(fx_path)
+        utils.rmtree(fx_path)
     with pytest.raises(SystemExit) as excinfo:
         wpt.main(argv=["install", "firefox", "browser", "--channel=nightly"])
     assert excinfo.value.code == 0
     assert os.path.exists(fx_path)
-    shutil.rmtree(fx_path)
+    utils.rmtree(fx_path)
 
 
 def test_files_changed(capsys):
diff --git a/tests/wpt/web-platform-tests/tools/wpt/tox.ini b/tests/wpt/web-platform-tests/tools/wpt/tox.ini
index 8e3e26e135b..7e6eb8e42a4 100644
--- a/tests/wpt/web-platform-tests/tools/wpt/tox.ini
+++ b/tests/wpt/web-platform-tests/tools/wpt/tox.ini
@@ -8,7 +8,8 @@ deps =
   pytest
   pytest-cov
   hypothesis
-  mock
+  # mock no longer supports Python 2 since v4
+  mock==3.*
   -r{toxinidir}/../wptrunner/requirements.txt
   -r{toxinidir}/../wptrunner/requirements_chrome.txt
   -r{toxinidir}/../wptrunner/requirements_firefox.txt
diff --git a/tests/wpt/web-platform-tests/tools/wpt/utils.py b/tests/wpt/web-platform-tests/tools/wpt/utils.py
index 18551481ab8..6608af754b2 100644
--- a/tests/wpt/web-platform-tests/tools/wpt/utils.py
+++ b/tests/wpt/web-platform-tests/tools/wpt/utils.py
@@ -1,5 +1,8 @@
+import errno
 import logging
 import os
+import shutil
+import stat
 import subprocess
 import tarfile
 import zipfile
@@ -95,3 +98,19 @@ def get(url):
     resp = requests.get(url, stream=True)
     resp.raise_for_status()
     return resp
+
+
+def rmtree(path):
+    # This works around two issues:
+    # 1. Cannot delete read-only files owned by us (e.g. files extracted from tarballs)
+    # 2. On Windows, we sometimes just need to retry in case the file handler
+    #    hasn't been fully released (a common issue).
+    def handle_remove_readonly(func, path, exc):
+        excvalue = exc[1]
+        if func in (os.rmdir, os.remove) and excvalue.errno == errno.EACCES:
+            os.chmod(path, stat.S_IRWXU | stat.S_IRWXG | stat.S_IRWXO)  # 0777
+            func(path)
+        else:
+            raise
+
+    return shutil.rmtree(path, onerror=handle_remove_readonly)
diff --git a/tests/wpt/web-platform-tests/tools/wptrunner/tox.ini b/tests/wpt/web-platform-tests/tools/wptrunner/tox.ini
index c544da7a95d..798f64a3e42 100644
--- a/tests/wpt/web-platform-tests/tools/wptrunner/tox.ini
+++ b/tests/wpt/web-platform-tests/tools/wptrunner/tox.ini
@@ -10,7 +10,8 @@ deps =
      pytest>=2.9
      pytest-cov
      pytest-xdist
-     mock
+     # mock no longer supports Python 2 since v4
+     mock==3.*
      -r{toxinidir}/requirements.txt
      chrome: -r{toxinidir}/requirements_chrome.txt
      edge: -r{toxinidir}/requirements_edge.txt