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Check disabled when building selectedcontent list #59059

Check disabled when building selectedcontent list
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Community-TC Integration / wpt-firefox-nightly-stability succeeded Apr 9, 2026 in 9m 37s

Community-TC (pull_request)

Verify that all tests affected by a pull request are stable when executed in firefox.

Details

View task in Taskcluster | View logs in Taskcluster | View task group in Taskcluster

Task Status

Started: 2026-04-09T01:00:09.520Z
Resolved: 2026-04-09T01:06:50.278Z
Task Execution Time: 6 minutes, 40 seconds, 758 milliseconds
Task Status: completed
Reason Resolved: completed
TaskId: VScjU2UcR3mbkwM0IR5jIA
RunId: 0

Artifacts

- public/logs/live_backing.log
- public/logs/live.log
- public/results/checkrun.md

WPT Command: python3 ./wpt run --channel=nightly --verify --verify-no-chaos-mode --verify-repeat-loop=0 --verify-repeat-restart=10 --github-checks-text-file=/home/test/artifacts/checkrun.md --affected base_head --log-mach-level=info --log-mach=- -y --no-pause --no-restart-on-unexpected --install-fonts --verify-log-full --no-headless --binary=/home/test/build/firefox/firefox firefox


[taskcluster 2026-04-09 01:00:09.588Z] Task ID: VScjU2UcR3mbkwM0IR5jIA
[taskcluster 2026-04-09 01:00:09.588Z] Worker ID: 1842477205682868766
[taskcluster 2026-04-09 01:00:09.588Z] Worker Group: us-central1-c
[taskcluster 2026-04-09 01:00:09.588Z] Worker Node Type: projects/757942385826/machineTypes/n2-standard-4
[taskcluster 2026-04-09 01:00:09.588Z] Worker Pool: proj-wpt/ci
[taskcluster 2026-04-09 01:00:09.588Z] Worker Version: 46.1.0
[taskcluster 2026-04-09 01:00:09.588Z] Public IP: 146.148.100.92
[taskcluster 2026-04-09 01:00:09.588Z] Hostname: proj-wpt-ci-wci7ptitruc6jcvu5fijcq

[taskcluster 2026-04-09 01:00:10.578Z] === Task Starting ===
+ '[' '' ']'
+ '[' -d /etc/profile.d ']'
+ for i in /etc/profile.d/*.sh
+ '[' -r /etc/profile.d/01-locale-fix.sh ']'
+ . /etc/profile.d/01-locale-fix.sh
+++ /usr/bin/locale-check C.UTF-8
++ eval
+ for i in /etc/profile.d/*.sh
+ '[' -r /etc/profile.d/apps-bin-path.sh ']'
+ . /etc/profile.d/apps-bin-path.sh

...(5682 lines hidden)...

  FAIL MutationObserver records during parsing of <select> with <selectedcontent>: test4 - assert_equals: test4 expected "<select>\n    <button>\n      <selectedcontent>two</selectedcontent>\n    </button>\n    <div>\n      <option>one</option>\n    </div>\n    <div>\n      <option selected=\"\">two</option>\n    </div>\n  </select>" but got "<select>\n    \n      \n    \n    \n      <option>one</option>\n    \n    \n      <option selected=\"\">two</option>\n    \n  </select>"
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-mutations.html:528:18
Test.prototype.step@http://web-platform.test:8000/resources/testharness.js:2869:25
test@http://web-platform.test:8000/resources/testharness.js:633:30
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-mutations.html:505:7
  FAIL MutationObserver records during parsing of <select> with <selectedcontent>: test5 - assert_equals: test5 expected "<select>\n    <option>option</option>\n    <button>\n      <selectedcontent>option</selectedcontent>\n    </button>\n  </select>" but got "<select>\n    <option>option</option>\n    \n      \n    \n  </select>"
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-mutations.html:528:18
Test.prototype.step@http://web-platform.test:8000/resources/testharness.js:2869:25
test@http://web-platform.test:8000/resources/testharness.js:633:30
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-mutations.html:505:7
  FAIL MutationObserver records during parsing of <select> with <selectedcontent>: test6 - assert_equals: test6 expected "<select multiple=\"\" size=\"1\">\n    <button>\n      <selectedcontent>\n        <selectedcontent></selectedcontent>\n      </selectedcontent>\n      <selectedcontent>\n        <selectedcontent></selectedcontent>\n      </selectedcontent>\n    </button>\n    <option>option</option>\n  </select>" but got "<select multiple=\"\" size=\"1\">\n    \n      \n        \n      \n      \n        \n      \n    \n    <option>option</option>\n  </select>"
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-mutations.html:528:18
Test.prototype.step@http://web-platform.test:8000/resources/testharness.js:2869:25
test@http://web-platform.test:8000/resources/testharness.js:633:30
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-mutations.html:505:7
  FAIL MutationObserver records during parsing of <select> with <selectedcontent>: test7 - assert_equals: test7 expected "<select>\n    <button>\n      <selectedcontent>one</selectedcontent>\n    </button>\n    <option>one</option>\n    <div></div>\n  <option selected=\"\">two</option><option selected=\"\">three</option></select>" but got "<select>\n    \n      \n    \n    <option>one</option>\n    \n  <option selected=\"\">two</option><option selected=\"\">three</option></select>"
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-mutations.html:528:18
Test.prototype.step@http://web-platform.test:8000/resources/testharness.js:2869:25
test@http://web-platform.test:8000/resources/testharness.js:633:30
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-mutations.html:505:7
  FAIL MutationObserver records during parsing of <select> with <selectedcontent>: test8 - assert_equals: test8 expected "<div class=\"container\"><select>\n    <button>\n      <selectedcontent>one</selectedcontent>\n    </button>\n    <option>one</option>\n    <option>two</option>\n  </select></div>" but got "<div class=\"container\"><select>\n    \n      \n    \n    <option>one</option>\n    <option>two</option>\n  </select></div>"
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-mutations.html:528:18
Test.prototype.step@http://web-platform.test:8000/resources/testharness.js:2869:25
test@http://web-platform.test:8000/resources/testharness.js:633:30
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-mutations.html:505:7
  FAIL MutationObserver records during parsing of <select> with <selectedcontent>: test1 - assert_equals: test1 expected "<select>\n    <button>\n      <selectedcontent><span>span</span> three</selectedcontent>\n    </button>\n    <option><span>span</span> one</option>\n    <option><span>span</span> two</option>\n    <option selected=\"\"><span>span</span> three</option>\n  </select>" but got "<select>\n    \n      \n    \n    <option>span one</option>\n    <option>span two</option>\n    <option selected=\"\">span three</option>\n  </select>"
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-mutations.html:528:18
Test.prototype.step@http://web-platform.test:8000/resources/testharness.js:2869:25
test@http://web-platform.test:8000/resources/testharness.js:633:30
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-mutations.html:505:7
  FAIL MutationObserver records during parsing of <select> with <selectedcontent>: test2 - assert_equals: test2 expected "<select>\n    <selectedcontent>option</selectedcontent>\n    <option>option</option>\n  </select>" but got "<select>\n    \n    <option>option</option>\n  </select>"
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-mutations.html:528:18
Test.prototype.step@http://web-platform.test:8000/resources/testharness.js:2869:25
test@http://web-platform.test:8000/resources/testharness.js:633:30
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-mutations.html:505:7
  FAIL MutationObserver records during parsing of <select> with <selectedcontent>: test3 - assert_equals: test3 expected "<select>\n    <button>\n      <selectedcontent>option</selectedcontent>\n      <selectedcontent>option</selectedcontent>\n    </button>\n    <option>option</option>\n  </select>" but got "<select>\n    \n      outer1\n        inner1\n      \n      outer2\n        inner2\n      \n    \n    <option>option</option>\n  </select>"
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-mutations.html:528:18
Test.prototype.step@http://web-platform.test:8000/resources/testharness.js:2869:25
test@http://web-platform.test:8000/resources/testharness.js:633:30
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-mutations.html:505:7
  FAIL MutationObserver records during parsing of <select> with <selectedcontent>: test4 - assert_equals: test4 expected "<select>\n    <button>\n      <selectedcontent>two</selectedcontent>\n    </button>\n    <div>\n      <option>one</option>\n    </div>\n    <div>\n      <option selected=\"\">two</option>\n    </div>\n  </select>" but got "<select>\n    \n      \n    \n    \n      <option>one</option>\n    \n    \n      <option selected=\"\">two</option>\n    \n  </select>"
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-mutations.html:528:18
Test.prototype.step@http://web-platform.test:8000/resources/testharness.js:2869:25
test@http://web-platform.test:8000/resources/testharness.js:633:30
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-mutations.html:505:7
  FAIL MutationObserver records during parsing of <select> with <selectedcontent>: test5 - assert_equals: test5 expected "<select>\n    <option>option</option>\n    <button>\n      <selectedcontent>option</selectedcontent>\n    </button>\n  </select>" but got "<select>\n    <option>option</option>\n    \n      \n    \n  </select>"
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-mutations.html:528:18
Test.prototype.step@http://web-platform.test:8000/resources/testharness.js:2869:25
test@http://web-platform.test:8000/resources/testharness.js:633:30
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-mutations.html:505:7
  FAIL MutationObserver records during parsing of <select> with <selectedcontent>: test6 - assert_equals: test6 expected "<select multiple=\"\" size=\"1\">\n    <button>\n      <selectedcontent>\n        <selectedcontent></selectedcontent>\n      </selectedcontent>\n      <selectedcontent>\n        <selectedcontent></selectedcontent>\n      </selectedcontent>\n    </button>\n    <option>option</option>\n  </select>" but got "<select multiple=\"\" size=\"1\">\n    \n      \n        \n      \n      \n        \n      \n    \n    <option>option</option>\n  </select>"
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-mutations.html:528:18
Test.prototype.step@http://web-platform.test:8000/resources/testharness.js:2869:25
test@http://web-platform.test:8000/resources/testharness.js:633:30
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-mutations.html:505:7
  FAIL MutationObserver records during parsing of <select> with <selectedcontent>: test7 - assert_equals: test7 expected "<select>\n    <button>\n      <selectedcontent>one</selectedcontent>\n    </button>\n    <option>one</option>\n    <div></div>\n  <option selected=\"\">two</option><option selected=\"\">three</option></select>" but got "<select>\n    \n      \n    \n    <option>one</option>\n    \n  <option selected=\"\">two</option><option selected=\"\">three</option></select>"
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-mutations.html:528:18
Test.prototype.step@http://web-platform.test:8000/resources/testharness.js:2869:25
test@http://web-platform.test:8000/resources/testharness.js:633:30
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-mutations.html:505:7
  FAIL MutationObserver records during parsing of <select> with <selectedcontent>: test8 - assert_equals: test8 expected "<div class=\"container\"><select>\n    <button>\n      <selectedcontent>one</selectedcontent>\n    </button>\n    <option>one</option>\n    <option>two</option>\n  </select></div>" but got "<div class=\"container\"><select>\n    \n      \n    \n    <option>one</option>\n    <option>two</option>\n  </select></div>"
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-mutations.html:528:18
Test.prototype.step@http://web-platform.test:8000/resources/testharness.js:2869:25
test@http://web-platform.test:8000/resources/testharness.js:633:30
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-mutations.html:505:7
  FAIL MutationObserver records during parsing of <select> with <selectedcontent>: test1 - assert_equals: test1 expected "<select>\n    <button>\n      <selectedcontent><span>span</span> three</selectedcontent>\n    </button>\n    <option><span>span</span> one</option>\n    <option><span>span</span> two</option>\n    <option selected=\"\"><span>span</span> three</option>\n  </select>" but got "<select>\n    \n      \n    \n    <option>span one</option>\n    <option>span two</option>\n    <option selected=\"\">span three</option>\n  </select>"
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-mutations.html:528:18
Test.prototype.step@http://web-platform.test:8000/resources/testharness.js:2869:25
test@http://web-platform.test:8000/resources/testharness.js:633:30
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-mutations.html:505:7
  FAIL MutationObserver records during parsing of <select> with <selectedcontent>: test2 - assert_equals: test2 expected "<select>\n    <selectedcontent>option</selectedcontent>\n    <option>option</option>\n  </select>" but got "<select>\n    \n    <option>option</option>\n  </select>"
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-mutations.html:528:18
Test.prototype.step@http://web-platform.test:8000/resources/testharness.js:2869:25
test@http://web-platform.test:8000/resources/testharness.js:633:30
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-mutations.html:505:7
  FAIL MutationObserver records during parsing of <select> with <selectedcontent>: test3 - assert_equals: test3 expected "<select>\n    <button>\n      <selectedcontent>option</selectedcontent>\n      <selectedcontent>option</selectedcontent>\n    </button>\n    <option>option</option>\n  </select>" but got "<select>\n    \n      outer1\n        inner1\n      \n      outer2\n        inner2\n      \n    \n    <option>option</option>\n  </select>"
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-mutations.html:528:18
Test.prototype.step@http://web-platform.test:8000/resources/testharness.js:2869:25
test@http://web-platform.test:8000/resources/testharness.js:633:30
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-mutations.html:505:7
  FAIL MutationObserver records during parsing of <select> with <selectedcontent>: test4 - assert_equals: test4 expected "<select>\n    <button>\n      <selectedcontent>two</selectedcontent>\n    </button>\n    <div>\n      <option>one</option>\n    </div>\n    <div>\n      <option selected=\"\">two</option>\n    </div>\n  </select>" but got "<select>\n    \n      \n    \n    \n      <option>one</option>\n    \n    \n      <option selected=\"\">two</option>\n    \n  </select>"
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-mutations.html:528:18
Test.prototype.step@http://web-platform.test:8000/resources/testharness.js:2869:25
test@http://web-platform.test:8000/resources/testharness.js:633:30
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-mutations.html:505:7
  FAIL MutationObserver records during parsing of <select> with <selectedcontent>: test5 - assert_equals: test5 expected "<select>\n    <option>option</option>\n    <button>\n      <selectedcontent>option</selectedcontent>\n    </button>\n  </select>" but got "<select>\n    <option>option</option>\n    \n      \n    \n  </select>"
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-mutations.html:528:18
Test.prototype.step@http://web-platform.test:8000/resources/testharness.js:2869:25
test@http://web-platform.test:8000/resources/testharness.js:633:30
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-mutations.html:505:7
  FAIL MutationObserver records during parsing of <select> with <selectedcontent>: test6 - assert_equals: test6 expected "<select multiple=\"\" size=\"1\">\n    <button>\n      <selectedcontent>\n        <selectedcontent></selectedcontent>\n      </selectedcontent>\n      <selectedcontent>\n        <selectedcontent></selectedcontent>\n      </selectedcontent>\n    </button>\n    <option>option</option>\n  </select>" but got "<select multiple=\"\" size=\"1\">\n    \n      \n        \n      \n      \n        \n      \n    \n    <option>option</option>\n  </select>"
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-mutations.html:528:18
Test.prototype.step@http://web-platform.test:8000/resources/testharness.js:2869:25
test@http://web-platform.test:8000/resources/testharness.js:633:30
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-mutations.html:505:7
  FAIL MutationObserver records during parsing of <select> with <selectedcontent>: test7 - assert_equals: test7 expected "<select>\n    <button>\n      <selectedcontent>one</selectedcontent>\n    </button>\n    <option>one</option>\n    <div></div>\n  <option selected=\"\">two</option><option selected=\"\">three</option></select>" but got "<select>\n    \n      \n    \n    <option>one</option>\n    \n  <option selected=\"\">two</option><option selected=\"\">three</option></select>"
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-mutations.html:528:18
Test.prototype.step@http://web-platform.test:8000/resources/testharness.js:2869:25
test@http://web-platform.test:8000/resources/testharness.js:633:30
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-mutations.html:505:7
  FAIL MutationObserver records during parsing of <select> with <selectedcontent>: test8 - assert_equals: test8 expected "<div class=\"container\"><select>\n    <button>\n      <selectedcontent>one</selectedcontent>\n    </button>\n    <option>one</option>\n    <option>two</option>\n  </select></div>" but got "<div class=\"container\"><select>\n    \n      \n    \n    <option>one</option>\n    <option>two</option>\n  </select></div>"
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-mutations.html:528:18
Test.prototype.step@http://web-platform.test:8000/resources/testharness.js:2869:25
test@http://web-platform.test:8000/resources/testharness.js:633:30
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-mutations.html:505:7
/html/semantics/forms/the-select-element/customizable-select/selectedcontent-nested.html
  FAIL Modification behavior when nesting selectedcontent elements. - can't access property "appendChild", button is null
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-nested.html:32:3
Test.prototype.step@http://web-platform.test:8000/resources/testharness.js:2869:25
test@http://web-platform.test:8000/resources/testharness.js:633:30
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-nested.html:14:5
  FAIL Modification behavior when nesting selectedcontent elements. - can't access property "appendChild", button is null
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-nested.html:32:3
Test.prototype.step@http://web-platform.test:8000/resources/testharness.js:2869:25
test@http://web-platform.test:8000/resources/testharness.js:633:30
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-nested.html:14:5
  FAIL Modification behavior when nesting selectedcontent elements. - can't access property "appendChild", button is null
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-nested.html:32:3
Test.prototype.step@http://web-platform.test:8000/resources/testharness.js:2869:25
test@http://web-platform.test:8000/resources/testharness.js:633:30
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-nested.html:14:5
  FAIL Modification behavior when nesting selectedcontent elements. - can't access property "appendChild", button is null
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-nested.html:32:3
Test.prototype.step@http://web-platform.test:8000/resources/testharness.js:2869:25
test@http://web-platform.test:8000/resources/testharness.js:633:30
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-nested.html:14:5
  FAIL Modification behavior when nesting selectedcontent elements. - can't access property "appendChild", button is null
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-nested.html:32:3
Test.prototype.step@http://web-platform.test:8000/resources/testharness.js:2869:25
test@http://web-platform.test:8000/resources/testharness.js:633:30
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-nested.html:14:5
  FAIL Modification behavior when nesting selectedcontent elements. - can't access property "appendChild", button is null
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-nested.html:32:3
Test.prototype.step@http://web-platform.test:8000/resources/testharness.js:2869:25
test@http://web-platform.test:8000/resources/testharness.js:633:30
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-nested.html:14:5
  FAIL Modification behavior when nesting selectedcontent elements. - can't access property "appendChild", button is null
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-nested.html:32:3
Test.prototype.step@http://web-platform.test:8000/resources/testharness.js:2869:25
test@http://web-platform.test:8000/resources/testharness.js:633:30
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-nested.html:14:5
  FAIL Modification behavior when nesting selectedcontent elements. - can't access property "appendChild", button is null
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-nested.html:32:3
Test.prototype.step@http://web-platform.test:8000/resources/testharness.js:2869:25
test@http://web-platform.test:8000/resources/testharness.js:633:30
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-nested.html:14:5
  FAIL Modification behavior when nesting selectedcontent elements. - can't access property "appendChild", button is null
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-nested.html:32:3
Test.prototype.step@http://web-platform.test:8000/resources/testharness.js:2869:25
test@http://web-platform.test:8000/resources/testharness.js:633:30
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-nested.html:14:5
  FAIL Modification behavior when nesting selectedcontent elements. - can't access property "appendChild", button is null
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-nested.html:32:3
Test.prototype.step@http://web-platform.test:8000/resources/testharness.js:2869:25
test@http://web-platform.test:8000/resources/testharness.js:633:30
@http://web-platform.test:8000/html/semantics/forms/the-select-element/customizable-select/selectedcontent-nested.html:14:5
 2:32.33 INFO Got 20 unexpected results, with 0 unexpected passes
 2:32.33 wptserve INFO Stopped http server on 127.0.0.1:8001
 2:32.33 wptserve INFO Stopped http server on 127.0.0.1:8003
 2:32.33 wptserve INFO Stopped http server on 127.0.0.1:8000
 2:32.33 wptserve INFO Stopped http server on 127.0.0.1:8002
 2:32.34 wptserve INFO Stopped http server on 127.0.0.1:8443
 2:32.34 wptserve INFO Stopped http server on 127.0.0.1:8444
 2:32.35 wptserve INFO Stopped http server on 127.0.0.1:8446
 2:32.35 wptserve INFO Stopped http server on 127.0.0.1:8445
 2:32.37 wptserve INFO Stopped http server on 127.0.0.1:9000
 2:32.37 wptserve INFO Stopped WebTransport over HTTP/3 server on 127.0.0.1:11000
 2:32.48 wptserve INFO Close on: (<AddressFamily.AF_INET: 2>, <SocketKind.SOCK_STREAM: 1>, 6, '', ('127.0.0.1', 8889))
 2:32.48 wptserve INFO Close on: (<AddressFamily.AF_INET: 2>, <SocketKind.SOCK_STREAM: 1>, 6, '', ('127.0.0.1', 8888))
 2:32.63 INFO Removed font: Ahem.ttf
 2:32.67 INFO Closing logging queue
 2:32.67 INFO queue closed
 2:32.68 INFO ::: Ran 10 of expected 10 iterations.
 2:32.68 INFO ## All results ##

 2:32.68 INFO ### /html/semantics/forms/the-select-element/customizable-select/selectedcontent-mutations.html ###
 2:32.68 INFO |                                       Subtest                                       | Results |                                                                                                                                                                                                                                             Messages                                                                                                                                                                                                                                             |
 2:32.68 INFO |-------------------------------------------------------------------------------------|---------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
 2:32.68 INFO |                                                                                     | OK      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
 2:32.68 INFO | `MutationObserver records during parsing of <select> with <selectedcontent>: test1` | FAIL    | `assert_equals: test1 expected "<select>\n    <button>\n      <selectedcontent><span>span</span> three</selectedcontent>\n    </button>\n    <option><span>span</span> one</option>\n    <option><span>span</span> two</option>\n    <option selected=\"\"><span>span</span> three</option>\n  </select>" but got "<select>\n    \n      \n    \n    <option>span one</option>\n    <option>span two</option>\n    <option selected=\"\">span three</option>\n  </select>"`                      |
 2:32.68 INFO | `MutationObserver records during parsing of <select> with <selectedcontent>: test2` | FAIL    | `assert_equals: test2 expected "<select>\n    <selectedcontent>option</selectedcontent>\n    <option>option</option>\n  </select>" but got "<select>\n    \n    <option>option</option>\n  </select>"`                                                                                                                                                                                                                                                                                           |
 2:32.68 INFO | `MutationObserver records during parsing of <select> with <selectedcontent>: test3` | FAIL    | `assert_equals: test3 expected "<select>\n    <button>\n      <selectedcontent>option</selectedcontent>\n      <selectedcontent>option</selectedcontent>\n    </button>\n    <option>option</option>\n  </select>" but got "<select>\n    \n      outer1\n        inner1\n      \n      outer2\n        inner2\n      \n    \n    <option>option</option>\n  </select>"`                                                                                                                         |
 2:32.68 INFO | `MutationObserver records during parsing of <select> with <selectedcontent>: test4` | FAIL    | `assert_equals: test4 expected "<select>\n    <button>\n      <selectedcontent>two</selectedcontent>\n    </button>\n    <div>\n      <option>one</option>\n    </div>\n    <div>\n      <option selected=\"\">two</option>\n    </div>\n  </select>" but got "<select>\n    \n      \n    \n    \n      <option>one</option>\n    \n    \n      <option selected=\"\">two</option>\n    \n  </select>"`                                                                                         |
 2:32.68 INFO | `MutationObserver records during parsing of <select> with <selectedcontent>: test5` | FAIL    | `assert_equals: test5 expected "<select>\n    <option>option</option>\n    <button>\n      <selectedcontent>option</selectedcontent>\n    </button>\n  </select>" but got "<select>\n    <option>option</option>\n    \n      \n    \n  </select>"`                                                                                                                                                                                                                                              |
 2:32.68 INFO | `MutationObserver records during parsing of <select> with <selectedcontent>: test6` | FAIL    | `assert_equals: test6 expected "<select multiple=\"\" size=\"1\">\n    <button>\n      <selectedcontent>\n        <selectedcontent></selectedcontent>\n      </selectedcontent>\n      <selectedcontent>\n        <selectedcontent></selectedcontent>\n      </selectedcontent>\n    </button>\n    <option>option</option>\n  </select>" but got "<select multiple=\"\" size=\"1\">\n    \n      \n        \n      \n      \n        \n      \n    \n    <option>option</option>\n  </select>"` |
 2:32.68 INFO | `MutationObserver records during parsing of <select> with <selectedcontent>: test7` | FAIL    | `assert_equals: test7 expected "<select>\n    <button>\n      <selectedcontent>one</selectedcontent>\n    </button>\n    <option>one</option>\n    <div></div>\n  <option selected=\"\">two</option><option selected=\"\">three</option></select>" but got "<select>\n    \n      \n    \n    <option>one</option>\n    \n  <option selected=\"\">two</option><option selected=\"\">three</option></select>"`                                                                                    |
 2:32.68 INFO | `MutationObserver records during parsing of <select> with <selectedcontent>: test8` | FAIL    | `assert_equals: test8 expected "<div class=\"container\"><select>\n    <button>\n      <selectedcontent>one</selectedcontent>\n    </button>\n    <option>one</option>\n    <option>two</option>\n  </select></div>" but got "<div class=\"container\"><select>\n    \n      \n    \n    <option>one</option>\n    <option>two</option>\n  </select></div>"`                                                                                                                                     |
 2:32.68 INFO 
 2:32.68 INFO ### /html/semantics/forms/the-select-element/customizable-select/selectedcontent-nested.html ###
 2:32.68 INFO |                            Subtest                             | Results |                        Messages                       |
 2:32.68 INFO |----------------------------------------------------------------|---------|-------------------------------------------------------|
 2:32.68 INFO |                                                                | OK      |                                                       |
 2:32.68 INFO | `Modification behavior when nesting selectedcontent elements.` | FAIL    | `can't access property "appendChild", button is null` |
 2:32.68 INFO 
 2:32.68 INFO ::: Running tests in a loop with restarts 10 times : PASS
 2:32.68 INFO :::
 2:32.68 INFO ::: Test verification PASS
 2:32.68 INFO :::
[taskcluster 2026-04-09 01:06:47.822Z] === Task Finished ===
[taskcluster 2026-04-09 01:06:48.265Z] Successful task run with exit code: 0 completed in 398.679 seconds