Filed by: nbeleuzu [at] mozilla.com
Parsed log: https://treeherder.mozilla.org/logviewer?job_id=341409171&repo=mozilla-central
Full log: https://firefox-ci-tc.services.mozilla.com/api/queue/v1/task/KgXMl-U6Rd-OPkb4VyH9Xg/runs/0/artifacts/public/logs/live_backing.log

[task 2021-06-01T12:24:19.170Z] 12:24:19     INFO - TEST-PASS | devtools/client/aboutdebugging/test/browser/browser_aboutdebugging_devtoolstoolbox_splitconsole_key.js | Split console is closed and no longer focused - 
[task 2021-06-01T12:24:19.170Z] 12:24:19     INFO - Close about:devtools-toolbox page
[task 2021-06-01T12:24:19.171Z] 12:24:19     INFO - Wait for removeTab
[task 2021-06-01T12:24:19.171Z] 12:24:19     INFO - Removing tab.
[task 2021-06-01T12:24:19.172Z] 12:24:19     INFO - Waiting for event: 'TabClose' on [object XULElement].
[task 2021-06-01T12:24:19.172Z] 12:24:19     INFO - Got event: 'TabClose' on [object XULElement].
[task 2021-06-01T12:24:19.173Z] 12:24:19     INFO - Tab removed and finished closing
[task 2021-06-01T12:24:19.173Z] 12:24:19     INFO - Wait for toolbox destroyed
[task 2021-06-01T12:24:19.174Z] 12:24:19     INFO - Wait until aboutdebugging is selected
[task 2021-06-01T12:24:19.174Z] 12:24:19     INFO - Wait until about:devtools-toolbox is removed from debug targets
[task 2021-06-01T12:24:19.174Z] 12:24:19     INFO - Console message: [JavaScript Error: "TypeError: can't access property "outerWidth", this.win is null" {file: "resource://devtools/client/framework/toolbox.js" line: 2863}]
[task 2021-06-01T12:24:19.175Z] 12:24:19     INFO - Buffered messages logged at 12:24:19
[task 2021-06-01T12:24:19.175Z] 12:24:19     INFO - Removing tab.
[task 2021-06-01T12:24:19.175Z] 12:24:19     INFO - Waiting for event: 'TabClose' on [object XULElement].
[task 2021-06-01T12:24:19.175Z] 12:24:19     INFO - Got event: 'TabClose' on [object XULElement].
[task 2021-06-01T12:24:19.176Z] 12:24:19     INFO - Tab removed and finished closing
[task 2021-06-01T12:24:19.176Z] 12:24:19     INFO - Buffered messages finished
[task 2021-06-01T12:24:19.178Z] 12:24:19     INFO - TEST-UNEXPECTED-FAIL | devtools/client/aboutdebugging/test/browser/browser_aboutdebugging_devtoolstoolbox_splitconsole_key.js | A promise chain failed to handle a rejection: can't access property "outerWidth", this.win is null - stack: openSplitConsole/<@resource://devtools/client/framework/toolbox.js:2863:9
[task 2021-06-01T12:24:19.178Z] 12:24:19     INFO - promise callback*openSplitConsole@resource://devtools/client/framework/toolbox.js:2859:40
[task 2021-06-01T12:24:19.178Z] 12:24:19     INFO - toggleSplitConsole@resource://devtools/client/framework/toolbox.js:2908:16
[task 2021-06-01T12:24:19.178Z] 12:24:19     INFO - _splitConsoleOnKeypress@resource://devtools/client/framework/toolbox.js:1582:12
[task 2021-06-01T12:24:19.178Z] 12:24:19     INFO - synthesizeKey@chrome://mochikit/content/tests/SimpleTest/EventUtils.js:1307:11
[task 2021-06-01T12:24:19.178Z] 12:24:19     INFO - @chrome://mochitests/content/browser/devtools/client/aboutdebugging/test/browser/browser_aboutdebugging_devtoolstoolbox_splitconsole_key.js:33:14
[task 2021-06-01T12:24:19.178Z] 12:24:19     INFO - Async*Tester_execTest/<@chrome://mochikit/content/browser-test.js:1089:34
[task 2021-06-01T12:24:19.178Z] 12:24:19     INFO - Tester_execTest@chrome://mochikit/content/browser-test.js:1129:11
[task 2021-06-01T12:24:19.178Z] 12:24:19     INFO - nextTest/<@chrome://mochikit/content/browser-test.js:946:14
[task 2021-06-01T12:24:19.178Z] 12:24:19     INFO - SimpleTest.waitForFocus/waitForFocusInner/focusedOrLoaded/<@chrome://mochikit/content/tests/SimpleTest/SimpleTest.js:1037:23
[task 2021-06-01T12:24:19.178Z] 12:24:19     INFO - Rejection date: Tue Jun 01 2021 12:24:18 GMT+0000 (Greenwich Mean Time) - false == true - JS frame :: resource://testing-common/PromiseTestUtils.jsm :: assertNoUncaughtRejections :: line 285
[task 2021-06-01T12:24:19.178Z] 12:24:19     INFO - Stack trace:
[task 2021-06-01T12:24:19.178Z] 12:24:19     INFO - resource://testing-common/PromiseTestUtils.jsm:assertNoUncaughtRejections:285
[task 2021-06-01T12:24:19.178Z] 12:24:19     INFO - chrome://mochikit/content/browser-test.js:Tester_execTest/<:1120
[task 2021-06-01T12:24:19.179Z] 12:24:19     INFO - chrome://mochikit/content/browser-test.js:Tester_execTest:1129
[task 2021-06-01T12:24:19.179Z] 12:24:19     INFO - chrome://mochikit/content/browser-test.js:nextTest/<:946
[task 2021-06-01T12:24:19.179Z] 12:24:19     INFO - chrome://mochikit/content/tests/SimpleTest/SimpleTest.js:SimpleTest.waitForFocus/waitForFocusInner/focusedOrLoaded/<:1037
[task 2021-06-01T12:24:19.179Z] 12:24:19     INFO - Leaving test bound 
[task 2021-06-01T12:24:19.180Z] 12:24:19     INFO - TEST-PASS | devtools/client/aboutdebugging/test/browser/browser_aboutdebugging_devtoolstoolbox_splitconsole_key.js | The main process DevToolsServer has no pending connection when the test ends - 
[task 2021-06-01T12:24:19.180Z] 12:24:19     INFO - GECKO(1498) | MEMORY STAT | vsize 8370MB | residentFast 633MB | heapAllocated 237MB
[task 2021-06-01T12:24:19.180Z] 12:24:19     INFO - TEST-OK | devtools/client/aboutdebugging/test/browser/browser_aboutdebugging_devtoolstoolbox_splitconsole_key.js | took 2537ms
[task 2021-06-01T12:24:19.181Z] 12:24:19     INFO - checking window state

Without this, the new pending call to watchResources throws because we close the toolbox while the console still initiates.

https://hg.mozilla.org/mozilla-central/rev/2bf840dd2c2b
https://hg.mozilla.org/mozilla-central/rev/ec73a04e7bd8

Set release status flags based on info from the regressing bug 1702511