Filed by: apavel [at] mozilla.com
Parsed log: https://treeherder.mozilla.org/logviewer.html#?job_id=255193384&repo=try
Full log: https://queue.taskcluster.net/v1/task/A8DEt3KFTqCZdLXFaDtEZA/runs/0/artifacts/public/logs/live_backing.log

02:51:11 INFO - TEST-START | dom/webauthn/tests/browser/browser_abort_visibility.js
02:51:11 INFO - GECKO(4528) | [Parent 6480, Main Thread] WARNING: Constructing RangeBoundary with invalid value: 'mRef || aOffset == 0', file z:/build/build/src/obj-firefox/dist/include\mozilla/RangeBoundary.h, line 79
02:51:11 INFO - GECKO(4528) | [Parent 6480, Main Thread] WARNING: Constructing RangeBoundary with invalid value: 'mRef || aOffset == 0', file z:/build/build/src/obj-firefox/dist/include\mozilla/RangeBoundary.h, line 79
02:51:11 INFO - GECKO(4528) | ### XPCOM_MEM_BLOAT_LOG defined -- logging bloat/leaks to c:\users\task_1562550124\appdata\local\temp\tmp3hrdaz.mozrunner\runtests_leaks_tab_pid9508.log
02:51:11 INFO - GECKO(4528) | [Parent 6480, Main Thread] WARNING: '!mSelection', file z:/build/build/src/editor/libeditor/EditorBase.cpp, line 4899

02:52:41 INFO - TEST-PASS | dom/webauthn/tests/browser/browser_abort_visibility.js | webauthn request pending -
02:52:41 INFO - Buffered messages finished
02:52:41 INFO - TEST-UNEXPECTED-FAIL | dom/webauthn/tests/browser/browser_abort_visibility.js | Test timed out -
02:52:41 INFO - GECKO(4528) | MEMORY STAT | vsize 2104195MB | vsizeMaxContiguous 65018039MB | residentFast 257MB | heapAllocated 76MB
02:52:41 INFO - TEST-OK | dom/webauthn/tests/browser/browser_abort_visibility.js | took 90194ms
02:52:41 INFO - GECKO(4528) | ++DOCSHELL 000001D49C948000 == 1 [pid = 3268] [id = {c4c0354a-f6af-4533-9180-e04ec914bae3}]
02:52:41 INFO - GECKO(4528) | ++DOMWINDOW == 1 (000001D4A3107020) [pid = 3268] [serial = 4] [outer = 0000000000000000]
02:52:41 INFO - GECKO(4528) | [Child 3268, Main Thread] WARNING: No active window: file z:/build/build/src/js/xpconnect/src/XPCJSContext.cpp, line 662
02:52:41 INFO - GECKO(4528) | ++DOMWINDOW == 2 (000001D4A2474000) [pid = 3268] [serial = 5] [outer = 000001D4A3107020]
02:52:41 INFO - GECKO(4528) | ++DOMWINDOW == 3 (000001D4A315DC00) [pid = 3268] [serial = 6] [outer = 000001D4A3107020]
02:52:41 INFO - GECKO(4528) | [Child 3268, Main Thread] WARNING: NS_ENSURE_SUCCESS(mStatus, *this) failed with result 0x80004005: file z:/build/build/src/obj-firefox/dist/include\nsIURIMutator.h, line 489
02:52:41 INFO - checking window state
02:52:41 INFO - Not taking screenshot here: see the one that was previously logged
02:52:41 INFO - TEST-UNEXPECTED-FAIL | dom/webauthn/tests/browser/browser_abort_visibility.js | Found a browser window after previous test timed out -
02:52:41 INFO - GECKO(4528) | must wait for focus
02:52:41 INFO - GECKO(4528) | JavaScript error: resource://testing-common/PromiseTestUtils.jsm, line 110: uncaught exception: Object
02:52:41 INFO - GECKO(4528) | [GPU 8432, Compositor] WARNING: Possibly dropping task posted to updater thread: file z:/build/build/src/gfx/layers/apz/src/APZUpdater.cpp, line 428
02:52:41 INFO - Not taking screenshot here: see the one that was previously logged
02:52:41 INFO - TEST-UNEXPECTED-FAIL | dom/webauthn/tests/browser/browser_abort_visibility.js | Uncaught exception received from previously timed out test - at chrome://mochitests/content/browser/dom/webauthn/tests/browser/browser_abort_visibility.js:199 - TypeError: SimpleTest.waitForFocus is not a function
02:52:41 INFO - Stack trace:
02:52:41 INFO - test_minimize_make/<@chrome://mochitests/content/browser/dom/webauthn/tests/browser/browser_abort_visibility.js:199:43
02:52:41 INFO - test_minimize_make@chrome://mochitests/content/browser/dom/webauthn/tests/browser/browser_abort_visibility.js:199:9

https://wiki.mozilla.org/Bug_Triage#Intermittent_Test_Failure_Cleanup

Recent failure log: https://treeherder.mozilla.org/logviewer.html#/jobs?job_id=264698018&repo=autoland&lineNumber=22381

[task 2019-09-03T08:58:29.664Z] 08:58:29 INFO - TEST-PASS | dom/webauthn/tests/browser/browser_abort_visibility.js | webauthn request pending -
[task 2019-09-03T08:58:29.664Z] 08:58:29 INFO - Console message: [JavaScript Error: "TypeError: this.manager.rootFrameLoader is null" {file: "resource://specialpowers/SpecialPowersParent.jsm" line: 605}]
[task 2019-09-03T08:58:29.664Z] 08:58:29 INFO - Console message: [JavaScript Error: "NS_ERROR_UNEXPECTED: "]
[task 2019-09-03T08:58:29.664Z] 08:58:29 INFO - Leaving test bound test_minimize_make
[task 2019-09-03T08:58:29.664Z] 08:58:29 INFO - Entering test bound test_minimize_get
[task 2019-09-03T08:58:29.665Z] 08:58:29 INFO - Console message: OpenGL compositor Initialized Succesfully.
[task 2019-09-03T08:58:29.665Z] 08:58:29 INFO - Version: 2.1 INTEL-12.9.22
[task 2019-09-03T08:58:29.665Z] 08:58:29 INFO - Vendor: Intel Inc.
[task 2019-09-03T08:58:29.665Z] 08:58:29 INFO - Renderer: Intel Iris OpenGL Engine
[task 2019-09-03T08:58:29.665Z] 08:58:29 INFO - FBO Texture Target: TEXTURE_2D
[task 2019-09-03T08:58:29.665Z] 08:58:29 INFO - Buffered messages logged at 08:57:09
[task 2019-09-03T08:58:29.665Z] 08:58:29 INFO - Attempting to get credential for origin: https://example.com
[task 2019-09-03T08:58:29.665Z] 08:58:29 INFO - Buffered messages finished
[task 2019-09-03T08:58:29.665Z] 08:58:29 INFO - TEST-UNEXPECTED-FAIL | dom/webauthn/tests/browser/browser_abort_visibility.js | Test timed out -
[task 2019-09-03T08:58:29.665Z] 08:58:29 INFO - GECKO(1957) | JavaScript error: resource://testing-common/PromiseTestUtils.jsm, line 112: uncaught exception: Object
[task 2019-09-03T08:58:29.665Z] 08:58:29 INFO - Console message: [JavaScript Error: "uncaught exception: Object" {file: "resource://testing-common/PromiseTestUtils.jsm" line: 112}]
[task 2019-09-03T08:58:29.665Z] 08:58:29 INFO - GECKO(1957) | MEMORY STAT vsizeMaxContiguous not supported in this build configuration.
[task 2019-09-03T08:58:29.665Z] 08:58:29 INFO - GECKO(1957) | MEMORY STAT | vsize 7719MB | residentFast 404MB | heapAllocated 107MB
[task 2019-09-03T08:58:29.665Z] 08:58:29 INFO - TEST-OK | dom/webauthn/tests/browser/browser_abort_visibility.js | took 90142ms
[task 2019-09-03T08:58:29.665Z] 08:58:29 INFO - GECKO(1957) | ++DOCSHELL 0x11be1c000 == 1 [pid = 1968] [id = {44122fb2-171c-5945-9774-a8baa2e74e96}]
[task 2019-09-03T08:58:29.665Z] 08:58:29 INFO - GECKO(1957) | ++DOMWINDOW == 1 (0x1043fd020) [pid = 1968] [serial = 1] [outer = 0x0]
[task 2019-09-03T08:58:29.665Z] 08:58:29 INFO - GECKO(1957) | ++DOMWINDOW == 2 (0x114a08800) [pid = 1968] [serial = 2] [outer = 0x1043fd020]
[task 2019-09-03T08:58:29.665Z] 08:58:29 INFO - checking window state
[task 2019-09-03T08:58:29.665Z] 08:58:29 INFO - Not taking screenshot here: see the one that was previously logged
[task 2019-09-03T08:58:29.665Z] 08:58:29 INFO - TEST-UNEXPECTED-FAIL | dom/webauthn/tests/browser/browser_abort_visibility.js | Found a browser window after previous test timed out -
[task 2019-09-03T08:58:29.665Z] 08:58:29 INFO - GECKO(1957) | ++DOMWINDOW == 3 (0x10432e800) [pid = 1968] [serial = 3] [outer = 0x1043fd020]
[task 2019-09-03T08:58:29.665Z] 08:58:29 INFO - GECKO(1957) | must wait for focus

I've observed this particular failure on experimental debian 10 docker test image on a permanent basis.

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