Bug: Intermittent toolkit/components/thumbnails/test/browser_thumbnails_removed_tab.js | single tracking bug
Status: RESOLVED
Priority: P5
Resolution: INCOMPLETE
Created: 2024-08-20 00:51:21+00:00
Resolved: 2024-09-16 12:03:57+00:00

**Filed by:** nfay [at] mozilla.com
**Parsed log:** https://treeherder.mozilla.org/logviewer?job_id=470966499&repo=mozilla-beta
**Full log:** https://firefox-ci-tc.services.mozilla.com/api/queue/v1/task/f7HZXdqGQS2tPsuidv1lcQ/runs/0/artifacts/public/logs/live_backing.log

---
```
[task 2024-08-19T23:57:58.218Z] 23:57:58     INFO - TEST-START | toolkit/components/thumbnails/test/browser_thumbnails_removed_tab.js
[task 2024-08-19T23:58:00.422Z] 23:58:00     INFO - TEST-INFO | started process screentopng
[task 2024-08-19T23:58:01.072Z] 23:58:01     INFO - TEST-INFO | screentopng: exit 0
[task 2024-08-19T23:58:01.073Z] 23:58:01     INFO - Buffered messages logged at 23:57:58
[task 2024-08-19T23:58:01.073Z] 23:58:01     INFO - Entering test bound thumbnails_bug1775638
[task 2024-08-19T23:58:01.073Z] 23:58:01     INFO - Buffered messages logged at 23:58:00
[task 2024-08-19T23:58:01.073Z] 23:58:01     INFO - TEST-PASS | toolkit/components/thumbnails/test/browser_thumbnails_removed_tab.js | undefined assertion name - 
[task 2024-08-19T23:58:01.074Z] 23:58:01     INFO - Leaving test bound thumbnails_bug1775638
[task 2024-08-19T23:58:01.074Z] 23:58:01     INFO - Buffered messages finished
[task 2024-08-19T23:58:01.074Z] 23:58:01     INFO - TEST-UNEXPECTED-FAIL | toolkit/components/thumbnails/test/browser_thumbnails_removed_tab.js | A promise chain failed to handle a rejection: aBrowser.browsingContext is null - stack: PageThumbs_captureAndStore@resource://gre/modules/PageThumbs.sys.mjs:433:9
[task 2024-08-19T23:58:01.074Z] 23:58:01     INFO - PageThumbs_captureAndStoreIfStale@resource://gre/modules/PageThumbs.sys.mjs:479:18
[task 2024-08-19T23:58:01.075Z] 23:58:01     INFO - async*_capture@chrome://browser/content/browser-thumbnails.js:136:24
[task 2024-08-19T23:58:01.076Z] 23:58:01     INFO - async*idleCallback@chrome://browser/content/browser-thumbnails.js:149:12
[task 2024-08-19T23:58:01.077Z] 23:58:01     INFO - requestIdleCallback handler*Thumbnails_delayedCapture/timeoutId<@chrome://browser/content/browser-thumbnails.js:155:47
[task 2024-08-19T23:58:01.078Z] 23:58:01     INFO - setTimeout handler*SimpleTest_setTimeoutShim@chrome://mochikit/content/tests/SimpleTest/SimpleTest.js:922:41
[task 2024-08-19T23:58:01.079Z] 23:58:01     INFO - Thumbnails_delayedCapture@chrome://browser/content/browser-thumbnails.js:154:31
[task 2024-08-19T23:58:01.080Z] 23:58:01     INFO - Thumbnails_handleEvent@chrome://browser/content/browser-thumbnails.js:77:14
[task 2024-08-19T23:58:01.081Z] 23:58:01     INFO - updateCurrentBrowser@chrome://browser/content/tabbrowser/tabbrowser.js:1421:16
[task 2024-08-19T23:58:01.082Z] 23:58:01     INFO - _setupEventListeners/<@chrome://browser/content/tabbrowser/tabbrowser.js:6237:16
[task 2024-08-19T23:58:01.083Z] 23:58:01     INFO - set selectedIndex@chrome://global/content/elements/tabbox.js:236:14
[task 2024-08-19T23:58:01.085Z] 23:58:01     INFO - set selectedPanel@chrome://global/content/elements/tabbox.js:246:54
[task 2024-08-19T23:58:01.086Z] 23:58:01     INFO - set selectedIndex@chrome://global/content/elements/tabbox.js:595:9
[task 2024-08-19T23:58:01.087Z] 23:58:01     INFO - set selectedItem@chrome://global/content/elements/tabbox.js:613:35
[task 2024-08-19T23:58:01.088Z] 23:58:01     INFO - set selectedTab@chrome://global/content/elements/tabbox.js:80:11
[task 2024-08-19T23:58:01.089Z] 23:58:01     INFO - set selectedTab@chrome://browser/content/tabbrowser/tabbrowser.js:473:7
[task 2024-08-19T23:58:01.090Z] 23:58:01     INFO - openNewForegroundTab/promises<@resource://testing-common/BrowserTestUtils.sys.mjs:219:61
[task 2024-08-19T23:58:01.091Z] 23:58:01     INFO - switchTab@resource://testing-common/BrowserTestUtils.sys.mjs:368:7
[task 2024-08-19T23:58:01.092Z] 23:58:01     INFO - openNewForegroundTab@resource://testing-common/BrowserTestUtils.sys.mjs:214:26
[task 2024-08-19T23:58:01.093Z] 23:58:01     INFO - thumbnails_bug1775638@chrome://mochitests/content/browser/toolkit/components/thumbnails/test/browser_thumbnails_removed_tab.js:5:38
[task 2024-08-19T23:58:01.094Z] 23:58:01     INFO - handleTask@chrome://mochikit/content/browser-test.js:1145:26
[task 2024-08-19T23:58:01.098Z] 23:58:01     INFO - _runTaskBasedTest@chrome://mochikit/content/browser-test.js:1217:18
[task 2024-08-19T23:58:01.100Z] 23:58:01     INFO - Tester_execTest@chrome://mochikit/content/browser-test.js:1358:14
[task 2024-08-19T23:58:01.101Z] 23:58:01     INFO - nextTest/<@chrome://mochikit/content/browser-test.js:1134:14
[task 2024-08-19T23:58:01.103Z] 23:58:01     INFO - SimpleTest.waitForFocus/<@chrome://mochikit/content/tests/SimpleTest/SimpleTest.js:1058:13
[task 2024-08-19T23:58:01.103Z] 23:58:01     INFO - Rejection date: Mon Aug 19 2024 23:58:00 GMT+0000 (Coordinated Universal Time) - false == true - 
[task 2024-08-19T23:58:01.104Z] 23:58:01     INFO - Stack trace:
[task 2024-08-19T23:58:01.106Z] 23:58:01     INFO - resource://testing-common/PromiseTestUtils.sys.mjs:assertNoUncaughtRejections:266
[task 2024-08-19T23:58:01.106Z] 23:58:01     INFO - chrome://mochikit/content/browser-test.js:nextTest:780
[task 2024-08-19T23:58:01.107Z] 23:58:01     INFO - chrome://mochikit/content/browser-test.js:testScope/test_finish/<:1811
[task 2024-08-19T23:58:01.108Z] 23:58:01     INFO - chrome://mochikit/content/browser-test.js:run:1731
[task 2024-08-19T23:58:01.108Z] 23:58:01     INFO - GECKO(6417) | JavaScript error: resource://gre/modules/PageThumbs.sys.mjs, line 433: TypeError: aBrowser.browsingContext is null
[task 2024-08-19T23:58:01.109Z] 23:58:01     INFO - Console message: [JavaScript Error: "TypeError: aBrowser.browsingContext is null" {file: "resource://gre/modules/PageThumbs.sys.mjs" line: 433}]
[task 2024-08-19T23:58:01.110Z] 23:58:01     INFO - _capture@chrome://browser/content/browser-thumbnails.js:136:24
[task 2024-08-19T23:58:01.111Z] 23:58:01     INFO - async*idleCallback@chrome://browser/content/browser-thumbnails.js:149:12
[task 2024-08-19T23:58:01.112Z] 23:58:01     INFO - requestIdleCallback handler*Thumbnails_delayedCapture/timeoutId<@chrome://browser/content/browser-thumbnails.js:155:47
[task 2024-08-19T23:58:01.112Z] 23:58:01     INFO - setTimeout handler*SimpleTest_setTimeoutShim@chrome://mochikit/content/tests/SimpleTest/SimpleTest.js:922:41
[task 2024-08-19T23:58:01.113Z] 23:58:01     INFO - Thumbnails_delayedCapture@chrome://browser/content/browser-thumbnails.js:154:31
[task 2024-08-19T23:58:01.114Z] 23:58:01     INFO - Thumbnails_handleEvent@chrome://browser/content/browser-thumbnails.js:77:14
[task 2024-08-19T23:58:01.115Z] 23:58:01     INFO - updateCurrentBrowser@chrome://browser/content/tabbrowser/tabbrowser.js:1421:16
[task 2024-08-19T23:58:01.116Z] 23:58:01     INFO - _setupEventListeners/<@chrome://browser/content/tabbrowser/tabbrowser.js:6237:16
[task 2024-08-19T23:58:01.116Z] 23:58:01     INFO - set selectedIndex@chrome://global/content/elements/tabbox.js:236:14
[task 2024-08-19T23:58:01.116Z] 23:58:01     INFO - set selectedPanel@chrome://global/content/elements/tabbox.js:246:54
[task 2024-08-19T23:58:01.116Z] 23:58:01     INFO - set selectedIndex@chrome://global/content/elements/tabbox.js:595:9
[task 2024-08-19T23:58:01.116Z] 23:58:01     INFO - set selectedItem@chrome://global/content/elements/tabbox.js:613:35
[task 2024-08-19T23:58:01.116Z] 23:58:01     INFO - set selectedTab@chrome://global/content/elements/tabbox.js:80:11
[task 2024-08-19T23:58:01.117Z] 23:58:01     INFO - set selectedTab@chrome://browser/content/tabbrowser/tabbrowser.js:473:7
[task 2024-08-19T23:58:01.117Z] 23:58:01     INFO - openNewForegroundTab/promises<@resource://testing-common/BrowserTestUtils.sys.mjs:219:61
[task 2024-08-19T23:58:01.117Z] 23:58:01     INFO - switchTab@resource://testing-common/BrowserTestUtils.sys.mjs:368:7
[task 2024-08-19T23:58:01.117Z] 23:58:01     INFO - openNewForegroundTab@resource://testing-common/BrowserTestUtils.sys.mjs:214:26
[task 2024-08-19T23:58:01.117Z] 23:58:01     INFO - thumbnails_bug1775638@chrome://mochitests/content/browser/toolkit/components/thumbnails/test/browser_thumbnails_removed_tab.js:5:38
[task 2024-08-19T23:58:01.117Z] 23:58:01     INFO - handleTask@chrome://mochikit/content/browser-test.js:1145:26
[task 2024-08-19T23:58:01.117Z] 23:58:01     INFO - _runTaskBasedTest@chrome://mochikit/content/browser-test.js:1217:18
[task 2024-08-19T23:58:01.117Z] 23:58:01     INFO - Tester_execTest@chrome://mochikit/content/browser-test.js:1358:14
[task 2024-08-19T23:58:01.117Z] 23:58:01     INFO - nextTest/<@chrome://mochikit/content/browser-test.js:1134:14
[task 2024-08-19T23:58:01.117Z] 23:58:01     INFO - SimpleTest.waitForFocus/<@chrome://mochikit/content/tests/SimpleTest/SimpleTest.js:1058:13
[task 2024-08-19T23:58:01.117Z] 23:58:01     INFO - 
[task 2024-08-19T23:58:01.117Z] 23:58:01     INFO - GECKO(6417) | MEMORY STAT | vsize 120590041MB | residentFast 1093MB
[task 2024-08-19T23:58:01.118Z] 23:58:01     INFO - TEST-OK | toolkit/components/thumbnails/test/browser_thumbnails_removed_tab.js | took 2446ms
[task 2024-08-19T23:58:01.118Z] 23:58:01     INFO - checking window state
[task 2024-08-19T23:58:01.118Z] 23:58:01     INFO - TEST-START | toolkit/components/thumbnails/test/browser_thumbnails_storage.js
```