2023930 - Intermittent browser/extensions/newtab/test/browser/browser_as_render.js | single tracking bug

Status: RESOLVED FIXED

(Firefox :: New Tab Page, defect, P5)

Description

[Treeherder Bug Filer]

Filed by: sstanca [at] mozilla.com
Parsed log: https://treeherder.mozilla.org/logviewer?job_id=554173565&repo=autoland&task=Qwnx2GjhTVOF3l_bufs7nw.0
Full log: https://firefox-ci-tc.services.mozilla.com/api/queue/v1/task/Qwnx2GjhTVOF3l_bufs7nw/runs/0/artifacts/public/logs/live_backing.log

---

[task 2026-03-17T15:16:19.401+00:00] 15:16:19     INFO - TEST-PASS | browser/extensions/newtab/test/browser/browser_as_load_location.js | took 2767ms
[task 2026-03-17T15:16:19.483+00:00] 15:16:19     INFO - TEST-START | browser/extensions/newtab/test/browser/browser_as_render.js
[task 2026-03-17T15:16:19.624+00:00] 15:16:19     INFO - GECKO(11146) | console.log: PrefsFeed: "Activation window evaluation skipped."
[task 2026-03-17T15:16:19.625+00:00] 15:16:19     INFO - GECKO(11146) | console.debug: PrefsFeed: "enabled:false, createdInstant:2026-03-17T15:00:43.306Z, variant: "
[task 2026-03-17T15:16:20.496+00:00] 15:16:20     INFO - GECKO(11146) | console.log: PrefsFeed: "Activation window evaluation skipped."
[task 2026-03-17T15:16:20.497+00:00] 15:16:20     INFO - GECKO(11146) | console.debug: PrefsFeed: "enabled:false, createdInstant:2026-03-17T15:00:43.306Z, variant: "
[taskcluster 2026-03-17T15:17:19.623Z] [taskcluster-proxy] Successfully refreshed taskcluster-proxy credentials: task-client/Qwnx2GjhTVOF3l_bufs7nw/0/on/us-central1-f/1521925220642117349/until/1773761839.564
[task 2026-03-17T15:18:19.584+00:00] 15:18:19     INFO - TEST-INFO | started process screentopng
[task 2026-03-17T15:18:19.824+00:00] 15:18:19     INFO - TEST-INFO | screentopng: exit 0
[task 2026-03-17T15:18:19.824+00:00] 15:18:19     INFO - Buffered messages logged at 15:16:19
[task 2026-03-17T15:18:19.825+00:00] 15:18:19     INFO - Entering test test_render_search_handoff
[task 2026-03-17T15:18:19.825+00:00] 15:18:19     INFO - Buffered messages finished
[task 2026-03-17T15:18:19.826+00:00] 15:18:19     INFO - TEST-UNEXPECTED-FAIL | browser/extensions/newtab/test/browser/browser_as_render.js | test_render_search_handoff - Test timed out
[task 2026-03-17T15:18:19.826+00:00] 15:18:19     INFO - TEST-UNEXPECTED-TIMEOUT | browser/extensions/newtab/test/browser/browser_as_render.js | Test timed out
[task 2026-03-17T15:18:19.826+00:00] 15:18:19     INFO - TEST-INFO took 120106ms
[task 2026-03-17T15:18:20.200+00:00] 15:18:20     INFO - GECKO(11146) | Completed ShutdownLeaks collections in process 11146
[task 2026-03-17T15:18:20.200+00:00] 15:18:20     INFO - TEST-START | Shutdown
[task 2026-03-17T15:18:20.201+00:00] 15:18:20     INFO - Browser Chrome Test Summary
[task 2026-03-17T15:18:20.202+00:00] 15:18:20     INFO - Passed:  19
[task 2026-03-17T15:18:20.202+00:00] 15:18:20     INFO - Failed:  1
[task 2026-03-17T15:18:20.203+00:00] 15:18:20     INFO - Todo:    0
[task 2026-03-17T15:18:20.203+00:00] 15:18:20     INFO - Mode:    e10s
[task 2026-03-17T15:18:20.204+00:00] 15:18:20     INFO - *** End BrowserChrome Test Results ***
[task 2026-03-17T15:18:20.343+00:00] 15:18:20     INFO - GECKO(11146) | 1773760700342	Marionette	TRACE	Received observer notification quit-application
[task 2026-03-17T15:18:20.343+00:00] 15:18:20     INFO - GECKO(11146) | 1773760700342	Marionette	TRACE	Application is shutting down with reason: "shutdown"
[task 2026-03-17T15:18:20.344+00:00] 15:18:20     INFO - GECKO(11146) | 1773760700343	Marionette	INFO	Stopped listening on port 2828
[task 2026-03-17T15:18:20.491+00:00] 15:18:20     INFO - GECKO(11146) | 1773760700490	Marionette	DEBUG	Marionette stopped listening
[task 2026-03-17T15:18:20.558+00:00] 15:18:20     INFO - Not taking screenshot here: see the one that was previously logged
[task 2026-03-17T15:18:20.560+00:00] 15:18:20     INFO - TEST-UNEXPECTED-FAIL | browser/extensions/newtab/test/browser/browser_as_render.js | test_render_search_handoff - Uncaught exception received from previously timed out test test_render_search_handoff - Error: The window unloaded while we were waiting for the browser to load - this should never happen.
[task 2026-03-17T15:18:20.560+00:00] 15:18:20     INFO - listener@resource://testing-common/BrowserTestUtils.sys.mjs:544:15
[task 2026-03-17T15:18:20.560+00:00] 15:18:20     INFO - EventListener.handleEvent*browserLoaded/<@resource://testing-common/BrowserTestUtils.sys.mjs:559:27
[task 2026-03-17T15:18:20.560+00:00] 15:18:20     INFO - browserLoaded@resource://testing-common/BrowserTestUtils.sys.mjs:509:12
[task 2026-03-17T15:18:20.560+00:00] 15:18:20     INFO - waitForPreloaded@chrome://mochitests/content/browser/browser/extensions/newtab/test/browser/head.js:77:28
[task 2026-03-17T15:18:20.560+00:00] 15:18:20     INFO - testTask@chrome://mochitests/content/browser/browser/extensions/newtab/test/browser/head.js:203:11
[task 2026-03-17T15:18:20.560+00:00] 15:18:20     INFO - async*handleTask@chrome://mochikit/content/browser-test.js:1376:26
[task 2026-03-17T15:18:20.560+00:00] 15:18:20     INFO - _runTaskBasedTest@chrome://mochikit/content/browser-test.js:1466:18
[task 2026-03-17T15:18:20.560+00:00] 15:18:20     INFO - Tester_execTest@chrome://mochikit/content/browser-test.js:1617:14
[task 2026-03-17T15:18:20.560+00:00] 15:18:20     INFO - nextTest/<@chrome://mochikit/content/browser-test.js:1356:14
[task 2026-03-17T15:18:20.560+00:00] 15:18:20     INFO - SimpleTest.waitForFocus/<@chrome://mochikit/content/tests/SimpleTest/SimpleTest.js:1060:13
[task 2026-03-17T15:18:20.561+00:00] 15:18:20     INFO - Entering test test_render_topsites
[task 2026-03-17T15:18:20.575+00:00] 15:18:20     INFO - GECKO(11146) | console.error: (new TypeError("can't access property \"fixupAndLoadURIString\", this.webNavigation is undefined", "chrome://global/content/elements/browser-custom-element.mjs", 921))
[task 2026-03-17T15:18:21.189+00:00] 15:18:21     INFO - GECKO(11146) | 1773760701188	Marionette	TRACE	Received observer notification xpcom-shutdown
[task 2026-03-17T15:18:21.218+00:00] 15:18:21     INFO - GECKO(11146) | 1773760701216	Marionette	TRACE	Received observer notification xpcom-shutdown-threads
[task 2026-03-17T15:18:23.612+00:00] 15:18:23     INFO - TEST-INFO | Main app process: exit 0

Comment 1

[Intermittent Failures Robot]

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

Repository breakdown:

• autoland: 7
• mozilla-central: 1

Table

	a11y_checks+swgl	no_variant	swgl	swr	swr-cf	trainhop	trainhop-rel
linux2404-x86_64/debug				1
linux2404-x86_64/opt							1
linux2404-x86_64/tsan				3	1
windows11-x86/opt		1
windows11-x86_64/opt							1

For more details, see:

https://treeherder.mozilla.org/intermittent-failures/bugdetails?bug=2023930&startday=2026-03-16&endday=2026-03-22&tree=all

Comment 2

[Intermittent Failures Robot]

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

Repository breakdown:

• autoland: 10
• mozilla-beta: 5
• mozilla-central: 3

Table

	a11y_checks+swgl	msix	no_variant	swgl	swr	trainhop	trainhop-beta	trainhop-rel
linux2404-x86_64/asan					1
linux2404-x86_64/ccov							2
linux2404-x86_64/opt					1
linux2404-x86_64/tsan					1
macosx1015-x86_64/debug			1
macosx1015-x86_64/opt			1				1	3
windows11-x86/opt			3
windows11-x86_64/debug		1	1
windows11-x86_64/opt		1	1

For more details, see:

https://treeherder.mozilla.org/intermittent-failures/bugdetails?bug=2023930&startday=2026-03-23&endday=2026-03-29&tree=all

Comment 3

[Intermittent Failures Robot]

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

Repository breakdown:

• autoland: 12
• try: 2
• mozilla-beta: 6
• mozilla-central: 2

Table

	a11y_checks+swgl	no_variant	standalone	swgl	swr	trainhop	trainhop-beta	trainhop-rel	trainhop-rel-cf
linux2404-x86_64/debug					1
linux2404-x86_64/opt							1	1
linux2404-x86_64/tsan					3
macosx1015-x86_64/opt		2					1	3
windows11-x86/opt		2
windows11-x86_64/ccov							1		1
windows11-x86_64/debug			1
windows11-x86_64/opt		3					2

For more details, see:

https://treeherder.mozilla.org/intermittent-failures/bugdetails?bug=2023930&startday=2026-03-30&endday=2026-04-05&tree=all

Comment 4

[Intermittent Failures Robot]

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

Repository breakdown:

• mozilla-beta: 3
• autoland: 17
• mozilla-central: 1

Table

	a11y_checks+swgl	msix	no_variant	swgl	swr	trainhop	trainhop-beta	trainhop-rel
linux2404-x86_64/opt					1
linux2404-x86_64/tsan					2
macosx1015-x86_64/debug			1
macosx1015-x86_64/opt			2				5	2
windows11-x86_64/debug		1
windows11-x86_64/opt		2	1				1	3

For more details, see:

https://treeherder.mozilla.org/intermittent-failures/bugdetails?bug=2023930&startday=2026-04-08&endday=2026-04-14&tree=all

Comment 5

[Intermittent Failures Robot]

15 failures were associated with this bug yesterday.

Repository breakdown:

• autoland: 15

Table

	a11y_checks+swgl	msix	no_variant	standalone	swgl	swr	trainhop	trainhop-rel
linux2404-x86_64/opt			3
linux2404-x86_64/tsan			2			1
macosx1015-x86_64/debug			1
macosx1015-x86_64/opt								1
windows11-x86/debug			1
windows11-x86/opt			1
windows11-x86_64/debug		2
windows11-x86_64/opt		1	2

For more details, see:

https://treeherder.mozilla.org/intermittent-failures/bugdetails?bug=2023930&startday=2026-04-17&endday=2026-04-17&tree=all

Comment 6

[Intermittent Failures Robot]

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

Repository breakdown:

• autoland: 25
• mozilla-beta: 2
• mozilla-central: 2

Table

	a11y_checks+swgl	msix	no_variant	standalone	swgl	swr	trainhop	trainhop-beta	trainhop-rel
linux2404-x86_64/opt			3			1
linux2404-x86_64/tsan			2			3
macosx1015-x86_64/debug			1
macosx1015-x86_64/opt			1					1	1
windows11-x86/debug			1
windows11-x86/opt			1
windows11-x86_64/debug		3		1
windows11-x86_64/opt		5	3					1	1

For more details, see:

https://treeherder.mozilla.org/intermittent-failures/bugdetails?bug=2023930&startday=2026-04-13&endday=2026-04-19&tree=all

Comment 7

[Intermittent Failures Robot]

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

Repository breakdown:

• autoland: 5
• mozilla-beta: 2

Table

	a11y-checks-swr	a11y_checks+swgl	msix	no_variant	standalone	swgl	swr	trainhop	trainhop-beta
linux2404-x86_64/debug							1
linux2404-x86_64/opt	1
windows11-x86/debug				1
windows11-x86_64/opt			2	1					1

For more details, see:

https://treeherder.mozilla.org/intermittent-failures/bugdetails?bug=2023930&startday=2026-04-20&endday=2026-04-26&tree=all

Comment 8

[Intermittent Failures Robot]

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

Repository breakdown:

• autoland: 4
• mozilla-central: 2

Table

	a11y_checks+swgl	no_variant	standalone	swgl	trainhop	trainhop-beta	trainhop-rel
linux2404-x86_64/opt						1	4
windows11-x86_64/opt							1

For more details, see:

https://treeherder.mozilla.org/intermittent-failures/bugdetails?bug=2023930&startday=2026-04-27&endday=2026-05-03&tree=all

Comment 9

[Intermittent Failures Robot]

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

Repository breakdown:

• mozilla-release: 1
• mozilla-beta: 2

Table

	a11y_checks+swgl	no_variant	standalone	swgl	swr	trainhop
linux2404-x86_64/tsan					1
windows11-x86/debug		1
windows11-x86_64/debug		1

For more details, see:

https://treeherder.mozilla.org/intermittent-failures/bugdetails?bug=2023930&startday=2026-05-04&endday=2026-05-10&tree=all

Comment 10

[Intermittent Failures Robot]

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

Repository breakdown:

• mozilla-beta: 4

Table

	msix	no_variant
windows11-x86/opt		1
windows11-x86_64/asan		1
windows11-x86_64/opt	1	1

For more details, see:

https://treeherder.mozilla.org/intermittent-failures/bugdetails?bug=2023930&startday=2026-05-11&endday=2026-05-17&tree=all

Comment 11

[Intermittent Failures Robot]

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

Repository breakdown:

• mozilla-release: 2

Table

	no_variant
windows11-x86/opt	1
windows11-x86_64/opt	1

For more details, see:

https://treeherder.mozilla.org/intermittent-failures/bugdetails?bug=2023930&startday=2026-05-18&endday=2026-05-24&tree=all

Comment 12

[Intermittent Failures Robot]

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

Repository breakdown:

• mozilla-release: 1

Table

	no_variant
windows11-x86_64/opt	1

For more details, see:

https://treeherder.mozilla.org/intermittent-failures/bugdetails?bug=2023930&startday=2026-06-01&endday=2026-06-07&tree=all

Comment 13

[Intermittent Failures Robot]

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

Repository breakdown:

• mozilla-release: 1

Table

	no_variant
windows11-x86/opt	1

For more details, see:

https://treeherder.mozilla.org/intermittent-failures/bugdetails?bug=2023930&startday=2026-06-08&endday=2026-06-14&tree=all

Comment 14

[Intermittent Failures Robot]

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

Repository breakdown:

• mozilla-central: 1

Table

	no_variant
windows11-x86_64/debug	1

For more details, see:

https://treeherder.mozilla.org/intermittent-failures/bugdetails?bug=2023930&startday=2026-06-22&endday=2026-06-28&tree=all

Comment 15

[BugBot [:suhaib / :marco]]

https://wiki.mozilla.org/Bug_Triage#Intermittent_Test_Failure_Cleanup
For more information, please visit BugBot documentation.

Comment 16

[Intermittent Failures Robot]

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

Repository breakdown:

• mozilla-beta: 1

Table

	no_variant
windows11-x86_64/debug	1

For more details, see:

https://treeherder.mozilla.org/intermittent-failures/bugdetails?bug=2023930&startday=2026-08-03&endday=2026-08-09&tree=all

Comment 17

[Florian Quèze [:florian]]

Attachment: Bug 2023930 - Stop browser_as_render.js testing the newtab that was preloaded before its pref push, r=#home-newtab-reviewers.

The preloaded about:newtab left behind by an earlier test is already mounting
<moz-urlbar> when add_setup turns browser.urlbar.newtab.featureGate off, and
never swaps it for the handoff search bar test_render_search_handoff drives.

Comment 18

[Pulsebot]

Pushed by [e-mail]:
https://github.com/mozilla-firefox/firefox/commit/0a36786a9a86
https://hg.mozilla.org/integration/autoland/rev/7ae9b5ccc75a
Stop browser_as_render.js testing the newtab that was preloaded before its pref push, r=mconley.

Comment 19

[Sandor Molnar[:smolnar]]

https://hg.mozilla.org/mozilla-central/rev/7ae9b5ccc75a

Comment 20

[Sandor Molnar[:smolnar]]

https://hg.mozilla.org/mozilla-central/rev/7ae9b5ccc75a

Comment 21

[Sandor Molnar[:smolnar]]

https://hg.mozilla.org/mozilla-central/rev/7ae9b5ccc75a

Comment 22

[Intermittent Failures Robot]

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

Repository breakdown:

• autoland: 1

Table

	a11y_checks+swgl	no_variant	standalone	swgl	swgl+urlbar_ipc	trainhop
linux2404-x86_64/tsan		1

For more details, see:

https://treeherder.mozilla.org/intermittent-failures/bugdetails?bug=2023930&startday=2026-09-21&endday=2026-09-27&tree=all