diff --git a/tests/wpt/metadata/MANIFEST.json b/tests/wpt/metadata/MANIFEST.json
index abb1a75f79a8..270ed0c1a9d5 100644
--- a/tests/wpt/metadata/MANIFEST.json
+++ b/tests/wpt/metadata/MANIFEST.json
@@ -135547,54 +135547,6 @@
      {}
     ]
    ],
-   "css/css-pseudo/first-line-change-inline-color-nested.html": [
-    [
-     "css/css-pseudo/first-line-change-inline-color-nested.html",
-     [
-      [
-       "/css/css-pseudo/first-line-change-inline-color-nested-ref.html",
-       "=="
-      ]
-     ],
-     {}
-    ]
-   ],
-   "css/css-pseudo/first-line-change-inline-color.html": [
-    [
-     "css/css-pseudo/first-line-change-inline-color.html",
-     [
-      [
-       "/css/css-pseudo/first-line-change-inline-color-ref.html",
-       "=="
-      ]
-     ],
-     {}
-    ]
-   ],
-   "css/css-pseudo/first-line-on-ancestor-block.html": [
-    [
-     "css/css-pseudo/first-line-on-ancestor-block.html",
-     [
-      [
-       "/css/css-pseudo/first-line-on-ancestor-block-ref.html",
-       "=="
-      ]
-     ],
-     {}
-    ]
-   ],
-   "css/css-pseudo/first-line-with-out-of-flow.html": [
-    [
-     "css/css-pseudo/first-line-with-out-of-flow.html",
-     [
-      [
-       "/css/css-pseudo/first-line-with-out-of-flow-ref.html",
-       "=="
-      ]
-     ],
-     {}
-    ]
-   ],
    "css/css-pseudo/marker-and-other-pseudo-elements.html": [
     [
      "css/css-pseudo/marker-and-other-pseudo-elements.html",
@@ -249955,18 +249907,6 @@
    "css/css-pseudo/first-line-and-placeholder-ref.html": [
     []
    ],
-   "css/css-pseudo/first-line-change-inline-color-nested-ref.html": [
-    []
-   ],
-   "css/css-pseudo/first-line-change-inline-color-ref.html": [
-    []
-   ],
-   "css/css-pseudo/first-line-on-ancestor-block-ref.html": [
-    []
-   ],
-   "css/css-pseudo/first-line-with-out-of-flow-ref.html": [
-    []
-   ],
    "css/css-pseudo/marker-and-other-pseudo-elements-ref.html": [
     []
    ],
@@ -348811,6 +348751,12 @@
      {}
     ]
    ],
+   "html/semantics/embedded-content/the-iframe-element/srcdoc_process_attributes.html": [
+    [
+     "html/semantics/embedded-content/the-iframe-element/srcdoc_process_attributes.html",
+     {}
+    ]
+   ],
    "html/semantics/embedded-content/the-img-element/404-response-with-actual-image-data.html": [
     [
      "html/semantics/embedded-content/the-img-element/404-response-with-actual-image-data.html",
@@ -557461,42 +557407,10 @@
    "2db3480feb5928c6a39fbf6084cf07bec0ba4767",
    "reftest"
   ],
-  "css/css-pseudo/first-line-change-inline-color-nested-ref.html": [
-   "84becd9a78d186ba3c0e658746fd56aef8039b74",
-   "support"
-  ],
-  "css/css-pseudo/first-line-change-inline-color-nested.html": [
-   "4a58f1ea5b623ffa5acd2993be16de399cd24127",
-   "reftest"
-  ],
-  "css/css-pseudo/first-line-change-inline-color-ref.html": [
-   "84becd9a78d186ba3c0e658746fd56aef8039b74",
-   "support"
-  ],
-  "css/css-pseudo/first-line-change-inline-color.html": [
-   "2a5be916b01d5d12eec1a4e81d912d95c7036916",
-   "reftest"
-  ],
   "css/css-pseudo/first-line-first-letter-insert-crash.html": [
    "17f035dedf1ef8df71918a1eacb01e1f0b80d46b",
    "testharness"
   ],
-  "css/css-pseudo/first-line-on-ancestor-block-ref.html": [
-   "7193bf25eb88c5443457480f7ce27782acd9473a",
-   "support"
-  ],
-  "css/css-pseudo/first-line-on-ancestor-block.html": [
-   "6b797107df80156b511b9dc58c5ee40d6114cfc4",
-   "reftest"
-  ],
-  "css/css-pseudo/first-line-with-out-of-flow-ref.html": [
-   "7193bf25eb88c5443457480f7ce27782acd9473a",
-   "support"
-  ],
-  "css/css-pseudo/first-line-with-out-of-flow.html": [
-   "798ecf8264e2ddb38257c6cb1174bcc069c6e6d1",
-   "reftest"
-  ],
   "css/css-pseudo/idlharness.html": [
    "4c113fc9091fb773cabd77f1419fac9a2e99650b",
    "testharness"
@@ -624961,6 +624875,10 @@
    "2f77dfe164df3737cbbabf4efce6e28028e62537",
    "testharness"
   ],
+  "html/semantics/embedded-content/the-iframe-element/srcdoc_process_attributes.html": [
+   "397c95a23911ef979718a3aa8b879d257803fb85",
+   "testharness"
+  ],
   "html/semantics/embedded-content/the-iframe-element/stash.py": [
    "0b8693a901152cc7a7f21de1fbdd191dce6078c3",
    "support"
@@ -632818,7 +632736,7 @@
    "support"
   ],
   "interfaces/animation-worklet.idl": [
-   "d223a745046f5ff65054306488285c031288d105",
+   "32988e11506d14930a27b3b77dc3a8435bdf4269",
    "support"
   ],
   "interfaces/appmanifest.idl": [
diff --git a/tests/wpt/metadata/css/css-transitions/properties-value-001.html.ini b/tests/wpt/metadata/css/css-transitions/properties-value-001.html.ini
index daaf3fa242e6..130c0181e438 100644
--- a/tests/wpt/metadata/css/css-transitions/properties-value-001.html.ini
+++ b/tests/wpt/metadata/css/css-transitions/properties-value-001.html.ini
@@ -1079,27 +1079,3 @@
   [text-indent percentage(%) / values]
     expected: FAIL
 
-  [padding-bottom length(ex) / values]
-    expected: FAIL
-
-  [padding-bottom length(cm) / values]
-    expected: FAIL
-
-  [margin-right length(in) / values]
-    expected: FAIL
-
-  [padding-left length(px) / values]
-    expected: FAIL
-
-  [padding-bottom length(mm) / values]
-    expected: FAIL
-
-  [margin-top length(px) / values]
-    expected: FAIL
-
-  [padding-left length(pt) / values]
-    expected: FAIL
-
-  [margin-right length(cm) / values]
-    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 ff5b07adb77b..e89282b04a19 100644
--- a/tests/wpt/metadata/css/cssom-view/elementsFromPoint-iframes.html.ini
+++ b/tests/wpt/metadata/css/cssom-view/elementsFromPoint-iframes.html.ini
@@ -1,5 +1,5 @@
 [elementsFromPoint-iframes.html]
-  expected: TIMEOUT
+  expected: CRASH
   [elementsFromPoint on the root document for points in iframe elements]
     expected: FAIL
 
diff --git a/tests/wpt/metadata/css/cssom-view/matchMedia-display-none-iframe.html.ini b/tests/wpt/metadata/css/cssom-view/matchMedia-display-none-iframe.html.ini
deleted file mode 100644
index e6e1f29e2743..000000000000
--- a/tests/wpt/metadata/css/cssom-view/matchMedia-display-none-iframe.html.ini
+++ /dev/null
@@ -1,2 +0,0 @@
-[matchMedia-display-none-iframe.html]
-  expected: ERROR
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 b3d5fd5662af..c5e7dd9675dd 100644
--- a/tests/wpt/metadata/fetch/content-type/response.window.js.ini
+++ b/tests/wpt/metadata/fetch/content-type/response.window.js.ini
@@ -312,18 +312,3 @@
   [<iframe>: separate response Content-Type: */* text/html]
     expected: FAIL
 
-  [<iframe>: combined response Content-Type: text/html */*]
-    expected: FAIL
-
-  [<iframe>: combined response Content-Type: text/html;charset=gbk text/plain text/html]
-    expected: FAIL
-
-  [<iframe>: combined response Content-Type: text/html;" text/plain]
-    expected: FAIL
-
-  [<iframe>: separate response Content-Type: text/html */*]
-    expected: FAIL
-
-  [<iframe>: separate response Content-Type: text/html;x=" 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 7d1d683ccbf7..d2df9b78483b 100644
--- a/tests/wpt/metadata/fetch/content-type/script.window.js.ini
+++ b/tests/wpt/metadata/fetch/content-type/script.window.js.ini
@@ -53,15 +53,6 @@
   [combined text/javascript ]
     expected: FAIL
 
-  [separate text/javascript;charset=windows-1252 error text/javascript]
-    expected: FAIL
-
   [separate text/javascript x/x]
     expected: FAIL
 
-  [separate text/javascript;charset=windows-1252  text/javascript]
-    expected: FAIL
-
-  [separate text/javascript ]
-    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 87c807a49ff9..ce73518c20aa 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%0C]
     expected: FAIL
 
+  [X-Content-Type-Options%3A%20'NosniFF']
+    expected: FAIL
+
+  [X-Content-Type-Options%3A%20%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
new file mode 100644
index 000000000000..87b07c3e6704
--- /dev/null
+++ b/tests/wpt/metadata/html/browsers/history/the-history-interface/traverse_the_history_1.html.ini
@@ -0,0 +1,4 @@
+[traverse_the_history_1.html]
+  [Multiple history traversals from the same task]
+    expected: FAIL
+
diff --git a/tests/wpt/metadata/html/browsers/history/the-history-interface/traverse_the_history_2.html.ini b/tests/wpt/metadata/html/browsers/history/the-history-interface/traverse_the_history_2.html.ini
deleted file mode 100644
index 75d75b4cda2e..000000000000
--- a/tests/wpt/metadata/html/browsers/history/the-history-interface/traverse_the_history_2.html.ini
+++ /dev/null
@@ -1,4 +0,0 @@
-[traverse_the_history_2.html]
-  [Multiple history traversals, last would be aborted]
-    expected: FAIL
-
diff --git a/tests/wpt/metadata/html/semantics/embedded-content/the-iframe-element/srcdoc_process_attributes.html.ini b/tests/wpt/metadata/html/semantics/embedded-content/the-iframe-element/srcdoc_process_attributes.html.ini
new file mode 100644
index 000000000000..d2ab05852084
--- /dev/null
+++ b/tests/wpt/metadata/html/semantics/embedded-content/the-iframe-element/srcdoc_process_attributes.html.ini
@@ -0,0 +1,11 @@
+[srcdoc_process_attributes.html]
+  expected: TIMEOUT
+  [Removing `srcdoc` attribute triggers attributes processing]
+    expected: FAIL
+
+  [Changing `srcdoc` (via property) triggers attributes processing]
+    expected: FAIL
+
+  [Adding `srcdoc` attribute triggers attributes processing]
+    expected: TIMEOUT
+
diff --git a/tests/wpt/metadata/html/syntax/parsing/DOMContentLoaded-defer.html.ini b/tests/wpt/metadata/html/syntax/parsing/DOMContentLoaded-defer.html.ini
new file mode 100644
index 000000000000..a9677391662b
--- /dev/null
+++ b/tests/wpt/metadata/html/syntax/parsing/DOMContentLoaded-defer.html.ini
@@ -0,0 +1,4 @@
+[DOMContentLoaded-defer.html]
+  [The end: DOMContentLoaded and defer scripts]
+    expected: FAIL
+
diff --git a/tests/wpt/metadata/resource-timing/resource_TAO_origin.htm.ini b/tests/wpt/metadata/resource-timing/resource_TAO_origin.htm.ini
index 1db2179e85f9..d9f5956bc52e 100644
--- a/tests/wpt/metadata/resource-timing/resource_TAO_origin.htm.ini
+++ b/tests/wpt/metadata/resource-timing/resource_TAO_origin.htm.ini
@@ -1,7 +1,4 @@
 [resource_TAO_origin.htm]
-  [domainLookupStart should not be 0 in timing-allow cross-origin request.]
-    expected: FAIL
-
   [domainLookupEnd should not be 0 in timing-allow cross-origin request.]
     expected: FAIL
 
diff --git a/tests/wpt/metadata/resource-timing/resource_TAO_zero.htm.ini b/tests/wpt/metadata/resource-timing/resource_TAO_zero.htm.ini
index a217df61431e..241deaa0d2fe 100644
--- a/tests/wpt/metadata/resource-timing/resource_TAO_zero.htm.ini
+++ b/tests/wpt/metadata/resource-timing/resource_TAO_zero.htm.ini
@@ -23,3 +23,6 @@
   [responseEnd should be greater than 0 in cross-origin request.]
     expected: FAIL
 
+  [domainLookupStart should be 0 in cross-origin request.]
+    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 088c57878f1d..4f17ba870c97 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
@@ -44,3 +44,9 @@
   [X Stitched sine-wave buffers at sample rate 43800 does not equal [0,0.06264832615852356,0.12505052983760834,0.18696144223213196,0.24813786149024963,0.308339387178421,0.36732959747314453,0.4248766601085663,0.480754554271698,0.5347436666488647,0.5866320133209229,0.6362156271934509,0.6832997798919678,0.7276994585990906,0.7692402601242065,0.8077589869499207...\] with an element-wise tolerance of {"absoluteThreshold":0.0038986,"relativeThreshold":0}.\n\tIndex\tActual\t\t\tExpected\t\tAbsError\t\tRelError\t\tTest threshold\n\t[30\]\t9.4836157560348511e-1\t9.5236867666244507e-1\t4.0071010589599609e-3\t4.2075103446311962e-3\t3.8985999999999999e-3\n\t[31\]\t9.2646563053131104e-1\t9.3139332532882690e-1\t4.9276947975158691e-3\t5.2906700783754857e-3\t3.8985999999999999e-3\n\t[32\]\t9.0087991952896118e-1\t9.0675884485244751e-1\t5.8789253234863281e-3\t6.4834496590358351e-3\t3.8985999999999999e-3\n\t[33\]\t8.7170630693435669e-1\t8.7856203317642212e-1\t6.8557262420654297e-3\t7.8033490899654511e-3\t3.8985999999999999e-3\n\t[34\]\t8.3906102180480957e-1\t8.4691369533538818e-1\t7.8526735305786133e-3\t9.2721059699818163e-3\t3.8985999999999999e-3\n\t...and 31037 more errors.\n\tMax AbsError of 9.8276454210281372e-1 at index of 39267.\n\t[39267\]\t-6.5667369214366148e-24\t-9.8276454210281372e-1\t9.8276454210281372e-1\t1.0000000000000000e+0\t3.8985999999999999e-3\n\tMax RelError of 3.3137802965303198e+0 at index of 1253.\n\t[1253\]\t-4.3022233992815018e-2\t-9.9732093513011932e-3\t3.3049024641513824e-2\t3.3137802965303198e+0\t3.8985999999999999e-3\n]
     expected: FAIL
 
+  [X Stitched sine-wave buffers at sample rate 43800 does not equal [0,0.06264832615852356,0.12505052983760834,0.18696144223213196,0.24813786149024963,0.308339387178421,0.36732959747314453,0.4248766601085663,0.480754554271698,0.5347436666488647,0.5866320133209229,0.6362156271934509,0.6832997798919678,0.7276994585990906,0.7692402601242065,0.8077589869499207...\] with an element-wise tolerance of {"absoluteThreshold":0.0038986,"relativeThreshold":0}.\n\tIndex\tActual\t\t\tExpected\t\tAbsError\t\tRelError\t\tTest threshold\n\t[30\]\t9.4836157560348511e-1\t9.5236867666244507e-1\t4.0071010589599609e-3\t4.2075103446311962e-3\t3.8985999999999999e-3\n\t[31\]\t9.2646563053131104e-1\t9.3139332532882690e-1\t4.9276947975158691e-3\t5.2906700783754857e-3\t3.8985999999999999e-3\n\t[32\]\t9.0087991952896118e-1\t9.0675884485244751e-1\t5.8789253234863281e-3\t6.4834496590358351e-3\t3.8985999999999999e-3\n\t[33\]\t8.7170630693435669e-1\t8.7856203317642212e-1\t6.8557262420654297e-3\t7.8033490899654511e-3\t3.8985999999999999e-3\n\t[34\]\t8.3906102180480957e-1\t8.4691369533538818e-1\t7.8526735305786133e-3\t9.2721059699818163e-3\t3.8985999999999999e-3\n\t...and 31037 more errors.\n\tMax AbsError of 1.4918195609552426e+11 at index of 20238.\n\t[20238\]\t-1.4918195609600000e+11\t-4.7574958205223083e-1\t1.4918195609552426e+11\t3.1357243752480292e+11\t3.8985999999999999e-3\n\tMax RelError of 3.1357243752480292e+11 at index of 20238.\n\t[20238\]\t-1.4918195609600000e+11\t-4.7574958205223083e-1\t1.4918195609552426e+11\t3.1357243752480292e+11\t3.8985999999999999e-3\n]
+    expected: FAIL
+
+  [X SNR (-183.0486244640611 dB) is not greater than or equal to 65.737. Got -183.0486244640611.]
+    expected: FAIL
+
diff --git a/tests/wpt/metadata/workers/WorkerGlobalScope-close.html.ini b/tests/wpt/metadata/workers/WorkerGlobalScope-close.html.ini
new file mode 100644
index 000000000000..fe8654e447c7
--- /dev/null
+++ b/tests/wpt/metadata/workers/WorkerGlobalScope-close.html.ini
@@ -0,0 +1,4 @@
+[WorkerGlobalScope-close.html]
+  [Test sending a message after closing.]
+    expected: FAIL
+
diff --git a/tests/wpt/metadata/workers/constructors/Worker/Worker-constructor.html.ini b/tests/wpt/metadata/workers/constructors/Worker/Worker-constructor.html.ini
deleted file mode 100644
index 80f9a4f15b8a..000000000000
--- a/tests/wpt/metadata/workers/constructors/Worker/Worker-constructor.html.ini
+++ /dev/null
@@ -1,2 +0,0 @@
-[Worker-constructor.html]
-  expected: ERROR
diff --git a/tests/wpt/web-platform-tests/css/css-pseudo/first-line-change-inline-color-nested-ref.html b/tests/wpt/web-platform-tests/css/css-pseudo/first-line-change-inline-color-nested-ref.html
deleted file mode 100644
index 84becd9a78d1..000000000000
--- a/tests/wpt/web-platform-tests/css/css-pseudo/first-line-change-inline-color-nested-ref.html
+++ /dev/null
@@ -1,2 +0,0 @@
-<!DOCTYPE html>
-<p style="color: blue">Blue <span style="color: green">This text should be green.</span> Blue</p>
diff --git a/tests/wpt/web-platform-tests/css/css-pseudo/first-line-change-inline-color-nested.html b/tests/wpt/web-platform-tests/css/css-pseudo/first-line-change-inline-color-nested.html
deleted file mode 100644
index 4a58f1ea5b62..000000000000
--- a/tests/wpt/web-platform-tests/css/css-pseudo/first-line-change-inline-color-nested.html
+++ /dev/null
@@ -1,23 +0,0 @@
-<!DOCTYPE html>
-<html class="reftest-wait">
-<link rel="help" href="https://drafts.csswg.org/css-pseudo-4/#first-line-pseudo">
-<link rel="match" href="first-line-change-inline-color-nested-ref.html">
-<style>
-  #block { color: green; }
-  #block::first-line { color: blue; }
-  .green { color: green; }
-</style>
-<div id="block">
-  <div>
-    <p>Blue <span id="target"><span>This text should be green.</span></span> Blue</p>
-  </div>
-</div>
-<script>
-requestAnimationFrame(() => {
-  requestAnimationFrame(() => {
-    target.className = 'green';
-    document.documentElement.removeAttribute('class');
-  });
-});
-</script>
-</html>
diff --git a/tests/wpt/web-platform-tests/css/css-pseudo/first-line-change-inline-color-ref.html b/tests/wpt/web-platform-tests/css/css-pseudo/first-line-change-inline-color-ref.html
deleted file mode 100644
index 84becd9a78d1..000000000000
--- a/tests/wpt/web-platform-tests/css/css-pseudo/first-line-change-inline-color-ref.html
+++ /dev/null
@@ -1,2 +0,0 @@
-<!DOCTYPE html>
-<p style="color: blue">Blue <span style="color: green">This text should be green.</span> Blue</p>
diff --git a/tests/wpt/web-platform-tests/css/css-pseudo/first-line-change-inline-color.html b/tests/wpt/web-platform-tests/css/css-pseudo/first-line-change-inline-color.html
deleted file mode 100644
index 2a5be916b01d..000000000000
--- a/tests/wpt/web-platform-tests/css/css-pseudo/first-line-change-inline-color.html
+++ /dev/null
@@ -1,23 +0,0 @@
-<!DOCTYPE html>
-<html class="reftest-wait">
-<link rel="help" href="https://drafts.csswg.org/css-pseudo-4/#first-line-pseudo">
-<link rel="match" href="first-line-change-inline-color-ref.html">
-<style>
-  #block { color: green; }
-  #block::first-line { color: blue; }
-  .green { color: green; }
-</style>
-<div id="block">
-  <div>
-    <p>Blue <span id="target">This text should be green.</span> Blue</p>
-  </div>
-</div>
-<script>
-requestAnimationFrame(() => {
-  requestAnimationFrame(() => {
-    target.className = 'green';
-    document.documentElement.removeAttribute('class');
-  });
-});
-</script>
-</html>
diff --git a/tests/wpt/web-platform-tests/css/css-pseudo/first-line-on-ancestor-block-ref.html b/tests/wpt/web-platform-tests/css/css-pseudo/first-line-on-ancestor-block-ref.html
deleted file mode 100644
index 7193bf25eb88..000000000000
--- a/tests/wpt/web-platform-tests/css/css-pseudo/first-line-on-ancestor-block-ref.html
+++ /dev/null
@@ -1,5 +0,0 @@
-<!DOCTYPE html>
-<div>
-  <span style="color: green">This text should be green.</span><br>
-  <span style="color: blue">This text should be blue.</span>
-</div>
diff --git a/tests/wpt/web-platform-tests/css/css-pseudo/first-line-on-ancestor-block.html b/tests/wpt/web-platform-tests/css/css-pseudo/first-line-on-ancestor-block.html
deleted file mode 100644
index 6b797107df80..000000000000
--- a/tests/wpt/web-platform-tests/css/css-pseudo/first-line-on-ancestor-block.html
+++ /dev/null
@@ -1,16 +0,0 @@
-<!DOCTYPE html>
-<link rel="help" href="https://drafts.csswg.org/css-pseudo-4/#first-line-pseudo">
-<link rel="match" href="first-line-on-ancestor-block-ref.html">
-<style>
-  #block::first-line { color: green; }
-</style>
-<div id="block">
-  <div>
-    <div style="color: blue">
-      <div>
-        <span><span>This text should be green.</span></span><br>
-        This text should be blue.
-      </div>
-    </div>
-  </div>
-</div>
diff --git a/tests/wpt/web-platform-tests/css/css-pseudo/first-line-with-out-of-flow-ref.html b/tests/wpt/web-platform-tests/css/css-pseudo/first-line-with-out-of-flow-ref.html
deleted file mode 100644
index 7193bf25eb88..000000000000
--- a/tests/wpt/web-platform-tests/css/css-pseudo/first-line-with-out-of-flow-ref.html
+++ /dev/null
@@ -1,5 +0,0 @@
-<!DOCTYPE html>
-<div>
-  <span style="color: green">This text should be green.</span><br>
-  <span style="color: blue">This text should be blue.</span>
-</div>
diff --git a/tests/wpt/web-platform-tests/css/css-pseudo/first-line-with-out-of-flow.html b/tests/wpt/web-platform-tests/css/css-pseudo/first-line-with-out-of-flow.html
deleted file mode 100644
index 798ecf8264e2..000000000000
--- a/tests/wpt/web-platform-tests/css/css-pseudo/first-line-with-out-of-flow.html
+++ /dev/null
@@ -1,20 +0,0 @@
-<!DOCTYPE html>
-<link rel="help" href="https://drafts.csswg.org/css-pseudo-4/#first-line-pseudo">
-<link rel="match" href="first-line-with-out-of-flow-ref.html">
-<style>
-  #block::first-line { color: green; }
-</style>
-<div id="block">
-  <div style="position: absolute"><br></div>
-  <div style="float: right"><br></div>
-  <div>
-    <div style="position: absolute"><br></div>
-    <div style="float: right"><br></div>
-    <div style="color: blue">
-      <div>
-        <span><span>This text should be green.</span></span><br>
-        This text should be blue.
-      </div>
-    </div>
-  </div>
-</div>
diff --git a/tests/wpt/web-platform-tests/html/semantics/embedded-content/the-iframe-element/srcdoc_process_attributes.html b/tests/wpt/web-platform-tests/html/semantics/embedded-content/the-iframe-element/srcdoc_process_attributes.html
new file mode 100644
index 000000000000..397c95a23911
--- /dev/null
+++ b/tests/wpt/web-platform-tests/html/semantics/embedded-content/the-iframe-element/srcdoc_process_attributes.html
@@ -0,0 +1,76 @@
+<!DOCTYPE html>
+<meta charset="utf-8">
+<title>Whenever `srcdoc` attribute is set, changed, or removed, the UA must process the &lt;iframe> attributes</title>
+<link rel="help" href="https://html.spec.whatwg.org/multipage/iframe-embed-object.html#the-iframe-element:process-the-iframe-attributes-2">
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<body>
+<script>
+function createIFrameWithBlobSrc() {
+  var iframe = document.createElement("iframe");
+  iframe.src = URL.createObjectURL(new Blob(["src"], {type: "text/html"}));
+  return iframe;
+}
+
+async_test(function(t) {
+  var iframe = createIFrameWithBlobSrc();
+  var isAdded = false;
+  iframe.onload = t.step_func(function() {
+    assert_equals(iframe.contentDocument.location.protocol, "blob:");
+    assert_equals(iframe.contentDocument.body.textContent, "src");
+
+    iframe.onload = t.step_func_done(function() {
+      assert_false(isAdded);
+      assert_equals(iframe.contentDocument.location.href, "about:srcdoc");
+      assert_equals(iframe.contentDocument.body.textContent, "srcdoc");
+    });
+
+    iframe.setAttribute("srcdoc", "srcdoc");
+    isAdded = true;
+  });
+
+  document.body.appendChild(iframe);
+}, "Adding `srcdoc` attribute triggers attributes processing");
+
+async_test(function(t) {
+  var iframe = createIFrameWithBlobSrc();
+  var isChanged = false;
+  iframe.srcdoc = "old";
+  iframe.onload = t.step_func(function() {
+    assert_equals(iframe.contentDocument.location.href, "about:srcdoc");
+    assert_equals(iframe.contentDocument.body.textContent, "old");
+
+    iframe.onload = t.step_func_done(function() {
+      assert_false(isChanged);
+      assert_equals(iframe.contentDocument.location.href, "about:srcdoc");
+      assert_equals(iframe.contentDocument.body.textContent, "new");
+    });
+
+    iframe.srcdoc = "new";
+    isChanged = true;
+  });
+
+  document.body.appendChild(iframe);
+}, "Changing `srcdoc` (via property) triggers attributes processing");
+
+async_test(function(t) {
+  var iframe = createIFrameWithBlobSrc();
+  var isRemoved = false;
+  iframe.srcdoc = "srcdoc";
+  iframe.onload = t.step_func(function() {
+    assert_equals(iframe.contentDocument.location.href, "about:srcdoc");
+    assert_equals(iframe.contentDocument.body.textContent, "srcdoc");
+
+    iframe.onload = t.step_func_done(function() {
+      assert_false(isRemoved);
+      assert_equals(iframe.contentDocument.location.protocol, "blob:");
+      assert_equals(iframe.contentDocument.body.textContent, "src");
+    });
+
+    iframe.removeAttribute("srcdoc");
+    isRemoved = true;
+  });
+
+  document.body.appendChild(iframe);
+}, "Removing `srcdoc` attribute triggers attributes processing");
+</script>
diff --git a/tests/wpt/web-platform-tests/interfaces/animation-worklet.idl b/tests/wpt/web-platform-tests/interfaces/animation-worklet.idl
index d223a745046f..32988e11506d 100644
--- a/tests/wpt/web-platform-tests/interfaces/animation-worklet.idl
+++ b/tests/wpt/web-platform-tests/interfaces/animation-worklet.idl
@@ -18,7 +18,7 @@ interface StatefulAnimator {
   any state();
 };
 
-[ Exposed=(AnimationWorklet, Worklet), Global=AnimationWorklet ]
+[ Global=(Worklet,AnimationWorklet), Exposed=AnimationWorklet ]
 interface AnimationWorkletGlobalScope : WorkletGlobalScope {
     void registerAnimator(DOMString name, AnimatorInstanceConstructor animatorCtor);
 };