2056646 - Perma [Tier 2] browser/base/content/test/fullscreen/browser_fullscreen_toplevel_warning.js | single tracking bug

Status: RESOLVED FIXED

(Core :: DOM: Core & HTML, defect)

Description

[Treeherder Bug Filer]

Filed by: smolnar [at] mozilla.com
Parsed log: https://treeherder.mozilla.org/logviewer?job_id=579992444&repo=autoland&task=aqC-iFvQS_e3fCQUarE0zw.0
Full log: https://firefox-ci-tc.services.mozilla.com/api/queue/v1/task/aqC-iFvQS_e3fCQUarE0zw/runs/0/artifacts/public/logs/live_backing.log

---

[task 2026-07-21T16:44:26.218+00:00] 16:44:26     INFO - TEST-PASS | browser/base/content/test/fullscreen/browser_fullscreen_toplevel_warning.js | test_fullscreen_warning_three_nested_origins - Top-level fullscreen: warning shows top-level domain
[task 2026-07-21T16:44:26.219+00:00] 16:44:26     INFO - Buffered messages finished
[task 2026-07-21T16:44:26.221+00:00] 16:44:26     INFO - TEST-UNEXPECTED-FAIL | browser/base/content/test/fullscreen/browser_fullscreen_toplevel_warning.js | test_fullscreen_warning_three_nested_origins - Node is not accessible via accessibility API: id: fullscreen-exit-button, tagName: html:button, className: 
[task 2026-07-21T16:44:26.221+00:00] 16:44:26     INFO - chrome://mochikit/content/browser-test.js:test_ok:1917
[task 2026-07-21T16:44:26.221+00:00] 16:44:26     INFO - chrome://mochikit/content/tests/SimpleTest/AccessibilityUtils.js:a11yFail:812
[task 2026-07-21T16:44:26.221+00:00] 16:44:26     INFO - chrome://mochikit/content/tests/SimpleTest/AccessibilityUtils.js:assertCanBeClicked:1224
[task 2026-07-21T16:44:26.221+00:00] 16:44:26     INFO - chrome://mochikit/content/tests/SimpleTest/AccessibilityUtils.js:runIfA11YChecks/this.AccessibilityUtils:1200
[task 2026-07-21T16:44:26.221+00:00] 16:44:26     INFO - chrome://mochikit/content/tests/SimpleTest/AccessibilityUtils.js:handleEvent:1323
[task 2026-07-21T16:44:26.221+00:00] 16:44:26     INFO - chrome://mochitests/content/browser/browser/base/content/test/fullscreen/browser_fullscreen_toplevel_warning.js:exitFullscreen:137
[task 2026-07-21T16:44:26.221+00:00] 16:44:26     INFO - chrome://mochitests/content/browser/browser/base/content/test/fullscreen/browser_fullscreen_toplevel_warning.js:test_fullscreen_warning_three_nested_origins/<:152
[task 2026-07-21T16:44:26.221+00:00] 16:44:26     INFO - resource://testing-common/BrowserTestUtils.sys.mjs:withNewTab:134
[task 2026-07-21T16:44:26.221+00:00] 16:44:26     INFO - chrome://mochitests/content/browser/browser/base/content/test/fullscreen/browser_fullscreen_toplevel_warning.js:test_fullscreen_warning_three_nested_origins:96
[task 2026-07-21T16:44:26.221+00:00] 16:44:26     INFO - chrome://mochikit/content/browser-test.js:handleTask:1402
[task 2026-07-21T16:44:26.221+00:00] 16:44:26     INFO - chrome://mochikit/content/browser-test.js:_runTaskBasedTest:1492
[task 2026-07-21T16:44:26.221+00:00] 16:44:26     INFO - chrome://mochikit/content/browser-test.js:Tester_execTest:1644
[task 2026-07-21T16:44:26.221+00:00] 16:44:26     INFO - chrome://mochikit/content/browser-test.js:nextTest/<:1382
[task 2026-07-21T16:44:26.221+00:00] 16:44:26     INFO - chrome://mochikit/content/tests/SimpleTest/SimpleTest.js:SimpleTest.waitForFocus/<:1060
[task 2026-07-21T16:44:26.222+00:00] 16:44:26     INFO - GECKO(9006) | ### XPCOM_MEM_BLOAT_LOG defined -- logging bloat/leaks to /tmp/tmpb67f3mc_.mozrunner/runtests_leaks_tab_pid9544.log
[task 2026-07-21T16:44:26.222+00:00] 16:44:26     INFO - GECKO(9006) | ### XPCOM_MEM_BLOAT_LOG defined -- logging bloat/leaks to /tmp/tmpb67f3mc_.mozrunner/runtests_leaks_tab_pid9544.log
[task 2026-07-21T16:44:26.292+00:00] 16:44:26     INFO - TEST-PASS | browser/base/content/test/fullscreen/browser_fullscreen_toplevel_warning.js | test_fullscreen_warning_three_nested_origins - Middle frame fullscreen: warning shows top-level domain

Comment 1

[BugBot [:suhaib / :marco]]

The Bugbug bot thinks this bug should belong to the 'Core::DOM: Core & HTML' component, and is moving the bug to that component. Please correct in case you think the bot is wrong.

Comment 2

[Intermittent Failures Robot]

24 failures were associated with this bug yesterday.

Repository breakdown:

• autoland: 23
• mozilla-central: 1

Table

	a11y-checks-swr	a11y_checks+swgl	no_variant	standalone	swgl
linux2404-x86_64/opt	24

For more details, see:

https://treeherder.mozilla.org/intermittent-failures/bugdetails?bug=2056646&startday=2026-07-21&endday=2026-07-21&tree=all

Comment 3

[BugBot [:suhaib / :marco]]

Set release status flags based on info from the regressing bug 2052047

Comment 4

[Intermittent Failures Robot]

39 failures were associated with this bug yesterday.

Repository breakdown:

• autoland: 34
• try: 1
• mozilla-central: 4

Table

	a11y-checks-swr	a11y_checks+swgl	no_variant	standalone	swgl
linux2404-x86_64/opt	39

For more details, see:

https://treeherder.mozilla.org/intermittent-failures/bugdetails?bug=2056646&startday=2026-07-22&endday=2026-07-22&tree=all

Comment 5

[Intermittent Failures Robot]

31 failures were associated with this bug yesterday.

Repository breakdown:

• autoland: 29
• mozilla-central: 2

Table

	a11y-checks-swr	a11y_checks+swgl	no_variant	standalone	swgl
linux2404-x86_64/opt	31

For more details, see:

https://treeherder.mozilla.org/intermittent-failures/bugdetails?bug=2056646&startday=2026-07-23&endday=2026-07-23&tree=all

Comment 6

[Intermittent Failures Robot]

31 failures were associated with this bug yesterday.

Repository breakdown:

• autoland: 29
• mozilla-central: 2

Table

	a11y-checks-swr	a11y_checks+swgl	no_variant	standalone	swgl
linux2404-x86_64/opt	31

For more details, see:

https://treeherder.mozilla.org/intermittent-failures/bugdetails?bug=2056646&startday=2026-07-24&endday=2026-07-24&tree=all

Comment 7

[Intermittent Failures Robot]

147 failures were associated with this bug in the last 7 days.
This is the #15 most frequent failure this week.

This failure happened more than 75 times this week! Resolving this bug is a very high priority.

Try to resolve this bug as soon as possible. If unresolved for 1 week, the affected test(s) may be disabled.

Repository breakdown:

• autoland: 134
• try: 1
• mozilla-central: 12

Table

	a11y-checks-swr	a11y_checks+swgl	no_variant	standalone	swgl
linux2404-x86_64/opt	147

For more details, see:

https://treeherder.mozilla.org/intermittent-failures/bugdetails?bug=2056646&startday=2026-07-20&endday=2026-07-26&tree=all

Comment 8

[Florian Quèze [:florian]]

Attachment: Bug 2056646 - Wait for the fullscreen warning animation before clicking its exit button, r=#firefox-desktop-core-reviewers,edgar.

The test clicked #fullscreen-exit-button from the MozDOMFullscreen:Entered
handler, ie. while nsGlobalWindowOuter::SetWidgetFullscreen still has the chrome
refresh driver frozen. No refresh tick can happen there, so the accessibility
tree update queued when the warning popover was shown never ran, and the
forceRefreshDriverTick() fallback in AccessibilityUtils silently did nothing.
The exit button had no accessible, and the a11y checks failed on the click.

Waiting for FullscreenWarningOnScreen instead puts the click after the refresh
driver has been thawed and the accessibility tree updated.

This also re-enables the test on the Nova configuration, where the same failure
was skipped for bug 2057924.

Comment 10

[Pulsebot]

Pushed by [e-mail]:
https://github.com/mozilla-firefox/firefox/commit/a21abb649db0
https://hg.mozilla.org/integration/autoland/rev/a1d0c2db642d
Wait for the fullscreen warning animation before clicking its exit button, r=firefox-desktop-core-reviewers ,Gijs.

Comment 11

[rperta]

https://hg.mozilla.org/mozilla-central/rev/a1d0c2db642d

Comment 13

[Intermittent Failures Robot]

9 failures were associated with this bug in the last 7 days.

Repository breakdown:

• autoland: 8
• mozilla-central: 1

Table

	a11y-checks-swr	a11y_checks+swgl	no_variant	standalone	swgl
linux2404-x86_64/opt	8
macosx1500-aarch64/debug			1

For more details, see:

https://treeherder.mozilla.org/intermittent-failures/bugdetails?bug=2056646&startday=2026-07-27&endday=2026-08-02&tree=all