Bug: Intermittent browser/components/privatebrowsing/test/browser/browser_privatebrowsing_about.js | Uncaught exception - at chrome://mochitests/content/browser/browser/components/privatebrowsing/test/browser/browser_privatebrowsing_about.js:18 - TypeError: ca
Status: RESOLVED
Priority: P5
Resolution: INCOMPLETE
Created: 2020-05-27 23:03:49+00:00
Resolved: 2020-06-23 17:01:08+00:00

**Filed by:** rmaries [at] mozilla.com
**Parsed log:** https://treeherder.mozilla.org/logviewer.html#?job_id=304011346&repo=autoland
**Full log:** https://firefox-ci-tc.services.mozilla.com/api/queue/v1/task/cZSpnpGTQM6K8jEErQVt3g/runs/0/artifacts/public/logs/live_backing.log

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[task 2020-05-27T22:19:17.316Z] 22:19:17     INFO - TEST-START | browser/components/privatebrowsing/test/browser/browser_privatebrowsing_about.js
[task 2020-05-27T22:19:17.377Z] 22:19:17     INFO - GECKO(5274) | [Parent 5274: Main Thread]: I/DocShellAndDOMWindowLeak ++DOCSHELL 0x7fba553dac00 == 13 [pid = 5274] [id = {2d313a43-3c4c-4a57-bde3-863f971381a3}]
[task 2020-05-27T22:19:17.378Z] 22:19:17     INFO - GECKO(5274) | [Parent 5274: Main Thread]: I/DocShellAndDOMWindowLeak ++DOMWINDOW == 28 (0x7fba56c03480) [pid = 5274] [serial = 28] [outer = (nil)]
[task 2020-05-27T22:19:17.378Z] 22:19:17     INFO - GECKO(5274) | [Parent 5274: Main Thread]: I/DocShellAndDOMWindowLeak ++DOMWINDOW == 29 (0x7fba553d5800) [pid = 5274] [serial = 29] [outer = 0x7fba56c03480]
[task 2020-05-27T22:19:17.393Z] 22:19:17     INFO - GECKO(5274) | [Parent 5274, Main Thread] WARNING: NS_ENSURE_TRUE(rootFrame) failed: file /builds/worker/checkouts/gecko/dom/base/nsGlobalWindowOuter.cpp, line 4260
[task 2020-05-27T22:19:17.595Z] 22:19:17     INFO - GECKO(5274) | [Parent 5274: Main Thread]: I/DocShellAndDOMWindowLeak ++DOCSHELL 0x7fba6dee0c00 == 14 [pid = 5274] [id = {a0c47d5d-8fbd-4555-92f6-8642769b2864}]
[task 2020-05-27T22:19:17.596Z] 22:19:17     INFO - GECKO(5274) | [Parent 5274: Main Thread]: I/DocShellAndDOMWindowLeak ++DOMWINDOW == 30 (0x7fba6ce84f10) [pid = 5274] [serial = 30] [outer = (nil)]
[task 2020-05-27T22:19:17.715Z] 22:19:17     INFO - GECKO(5274) | ### XPCOM_MEM_BLOAT_LOG defined -- logging bloat/leaks to /tmp/tmpl6cJ1m.mozrunner/runtests_leaks_tab_pid5722.log
[task 2020-05-27T22:19:17.716Z] 22:19:17     INFO - GECKO(5274) | [5722, Main Thread] WARNING: XPCOM_MEM_BLOAT_LOG is set, disabling native allocations.: file /builds/worker/checkouts/gecko/tools/profiler/core/platform.cpp, line 243
[task 2020-05-27T22:19:17.832Z] 22:19:17     INFO - GECKO(5274) | [Parent 5274: Main Thread]: I/DocShellAndDOMWindowLeak ++DOMWINDOW == 31 (0x7fba6deec000) [pid = 5274] [serial = 31] [outer = 0x7fba6ce84f10]
[task 2020-05-27T22:19:18.171Z] 22:19:18     INFO - GECKO(5274) | [Child 5376: Main Thread]: I/DocShellAndDOMWindowLeak --DOMWINDOW == 1 (0x7f500793c400) [pid = 5376] [serial = 3] [outer = (nil)] [url = about:blank]
[task 2020-05-27T22:19:18.171Z] 22:19:18     INFO - GECKO(5274) | [Child 5376: Main Thread]: I/DocShellAndDOMWindowLeak --DOMWINDOW == 0 (0x7f5008293800) [pid = 5376] [serial = 4] [outer = (nil)] [url = about:blank]
[task 2020-05-27T22:19:18.247Z] 22:19:18     INFO - GECKO(5274) | [Child 5376: Main Thread]: I/DocShellAndDOMWindowLeak ++DOCSHELL 0x7f500793a000 == 1 [pid = 5376] [id = {e3555a41-8971-4ce2-8899-7452c6f8c879}]
[task 2020-05-27T22:19:18.247Z] 22:19:18     INFO - GECKO(5274) | [Child 5376: Main Thread]: I/DocShellAndDOMWindowLeak ++DOMWINDOW == 1 (0x7f5023693180) [pid = 5376] [serial = 5] [outer = (nil)]
[task 2020-05-27T22:19:18.248Z] 22:19:18     INFO - GECKO(5274) | [Child 5376: Main Thread]: I/DocShellAndDOMWindowLeak ++DOMWINDOW == 2 (0x7f500793b000) [pid = 5376] [serial = 6] [outer = 0x7f5023693180]
[task 2020-05-27T22:19:18.303Z] 22:19:18     INFO - GECKO(5274) | [Child 5722, Main Thread] WARNING: could not set real-time limit at process startup: file /builds/worker/checkouts/gecko/dom/ipc/ContentChild.cpp, line 1628
[task 2020-05-27T22:19:18.304Z] 22:19:18     INFO - GECKO(5274) | [Child 5722: Main Thread]: I/DocShellAndDOMWindowLeak ++DOCSHELL 0x7f8907bd4400 == 1 [pid = 5722] [id = {35e4044c-8229-4033-a5c5-87baa03758b5}]
[task 2020-05-27T22:19:18.313Z] 22:19:18     INFO - GECKO(5274) | [Child 5376: Main Thread]: I/DocShellAndDOMWindowLeak ++DOMWINDOW == 3 (0x7f5008296c00) [pid = 5376] [serial = 7] [outer = 0x7f5023693180]
[task 2020-05-27T22:19:18.320Z] 22:19:18     INFO - GECKO(5274) | [Child 5722: Main Thread]: I/DocShellAndDOMWindowLeak ++DOMWINDOW == 1 (0x7f891d893350) [pid = 5722] [serial = 1] [outer = (nil)]
[task 2020-05-27T22:19:18.321Z] 22:19:18     INFO - GECKO(5274) | [Child 5722: Main Thread]: I/DocShellAndDOMWindowLeak ++DOMWINDOW == 2 (0x7f89024bd000) [pid = 5722] [serial = 2] [outer = 0x7f891d893350]
[task 2020-05-27T22:19:18.530Z] 22:19:18     INFO - GECKO(5274) | [Child 5722: Main Thread]: I/DocShellAndDOMWindowLeak ++DOMWINDOW == 3 (0x7f89024c6400) [pid = 5722] [serial = 3] [outer = 0x7f891d893350]
[task 2020-05-27T22:19:18.734Z] 22:19:18     INFO - TEST-INFO | started process screentopng
[task 2020-05-27T22:19:19.106Z] 22:19:19     INFO - TEST-INFO | screentopng: exit 0
[task 2020-05-27T22:19:19.107Z] 22:19:19     INFO - Buffered messages logged at 22:19:17
[task 2020-05-27T22:19:19.107Z] 22:19:19     INFO - Entering test bound setup
[task 2020-05-27T22:19:19.108Z] 22:19:19     INFO - Leaving test bound setup
[task 2020-05-27T22:19:19.109Z] 22:19:19     INFO - Entering test bound test_myths_link
[task 2020-05-27T22:19:19.109Z] 22:19:19     INFO - Buffered messages finished
[task 2020-05-27T22:19:19.110Z] 22:19:19     INFO - TEST-UNEXPECTED-FAIL | browser/components/privatebrowsing/test/browser/browser_privatebrowsing_about.js | Uncaught exception - at chrome://mochitests/content/browser/browser/components/privatebrowsing/test/browser/browser_privatebrowsing_about.js:18 - TypeError: can't access property "click", content.document.getElementById(...) is null
[task 2020-05-27T22:19:19.110Z] 22:19:19     INFO - Stack trace:
[task 2020-05-27T22:19:19.111Z] 22:19:19     INFO - @chrome://mochitests/content/browser/browser/components/privatebrowsing/test/browser/browser_privatebrowsing_about.js:18:22
[task 2020-05-27T22:19:19.111Z] 22:19:19     INFO - execute@resource://specialpowers/SpecialPowersSandbox.jsm:141:12
[task 2020-05-27T22:19:19.111Z] 22:19:19     INFO - _spawnTask@resource://specialpowers/SpecialPowersChild.jsm:1757:15
[task 2020-05-27T22:19:19.111Z] 22:19:19     INFO - receiveMessage@resource://specialpowers/SpecialPowersChild.jsm:281:21