Bug: Intermittent JavaScript error: resource:///modules/AsyncTabSwitcher.jsm, line 503: Error: Assertion failure | After "Assertion failure" | DON'T USE FOR CLASSIFICATION
Status: NEW
Priority: P5
Created: 2020-06-19 20:38:32+00:00
Resolved: 2022-10-12 00:10:27+00:00

**Filed by:** nbeleuzu [at] mozilla.com
**Parsed log:** https://treeherder.mozilla.org/logviewer.html#?job_id=306914073&repo=mozilla-central
**Full log:** https://firefox-ci-tc.services.mozilla.com/api/queue/v1/task/CXtgVi8JR5u50ZPeTM_Yuw/runs/0/artifacts/public/logs/live_backing.log

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[task 2020-06-19T16:54:10.177Z] 16:54:10     INFO - GECKO(10236) | [Parent 10512, Main Thread] WARNING: IPC message discarded: actor cannot send: file /builds/worker/checkouts/gecko/ipc/glue/ProtocolUtils.cpp, line 470
[task 2020-06-19T16:54:10.183Z] 16:54:10     INFO - GECKO(10236) | [Parent 10512: Main Thread]: I/DocShellAndDOMWindowLeak ++DOCSHELL 0000013B5E862400 == 30 [pid = 10512] [id = {eb5f12e9-5c8f-46e7-b02d-58d9c795f9f1}]
[task 2020-06-19T16:54:10.183Z] 16:54:10     INFO - GECKO(10236) | [Parent 10512: Main Thread]: I/DocShellAndDOMWindowLeak ++DOMWINDOW == 80 (0000013B6533CDE0) [pid = 10512] [serial = 1024] [outer = 0000000000000000]
[task 2020-06-19T16:54:10.183Z] 16:54:10     INFO - GECKO(10236) | [Parent 10512: Main Thread]: I/DocShellAndDOMWindowLeak ++DOMWINDOW == 81 (0000013B62C7BC00) [pid = 10512] [serial = 1025] [outer = 0000013B6533CDE0]
[task 2020-06-19T16:54:10.207Z] 16:54:10     INFO - GECKO(10236) | Assertion failure
[task 2020-06-19T16:54:10.208Z] 16:54:10     INFO - GECKO(10236) | assert@resource:///modules/AsyncTabSwitcher.jsm:499:36
[task 2020-06-19T16:54:10.208Z] 16:54:10     INFO - GECKO(10236) | finish@resource:///modules/AsyncTabSwitcher.jsm:331:10
[task 2020-06-19T16:54:10.209Z] 16:54:10     INFO - GECKO(10236) | postActions@resource:///modules/AsyncTabSwitcher.jsm:697:12
[task 2020-06-19T16:54:10.209Z] 16:54:10     INFO - GECKO(10236) | handleEvent@resource:///modules/AsyncTabSwitcher.jsm:1116:12
[task 2020-06-19T16:54:10.209Z] 16:54:10     INFO - GECKO(10236) | updateBrowserRemoteness@chrome://browser/content/tabbrowser.js:1931:11
[task 2020-06-19T16:54:10.209Z] 16:54:10     INFO - GECKO(10236) | onBackgroundBrowserCrash@resource:///modules/ContentCrashHandlers.jsm:274:14
[task 2020-06-19T16:54:10.209Z] 16:54:10     INFO - GECKO(10236) | onTabCrashed@chrome://browser/content/tabbrowser.js:5447:27
[task 2020-06-19T16:54:10.210Z] 16:54:10     INFO - GECKO(10236) | JavaScript error: resource:///modules/AsyncTabSwitcher.jsm, line 503: Error: Assertion failure
[task 2020-06-19T16:54:10.220Z] 16:54:10     INFO - GECKO(10236) | [Parent 10512, Main Thread] WARNING: IPC message discarded: actor cannot send: file /builds/worker/checkouts/gecko/ipc/glue/ProtocolUtils.cpp, line 470
[task 2020-06-19T16:54:10.220Z] 16:54:10     INFO - GECKO(10236) | [Parent 10512, Main Thread] WARNING: IPC message discarded: actor cannot send: file /builds/worker/checkouts/gecko/ipc/glue/ProtocolUtils.cpp, line 470
[task 2020-06-19T16:54:10.220Z] 16:54:10     INFO - GECKO(10236) | [Parent 10512: Main Thread]: I/DocShellAndDOMWindowLeak ++DOCSHELL 0000013B658A6000 == 31 [pid = 10512] [id = {55902ad9-dea5-436d-be1d-872de6be383d}]
[task 2020-06-19T16:54:10.220Z] 16:54:10     INFO - GECKO(10236) | [Parent 10512: Main Thread]: I/DocShellAndDOMWindowLeak ++DOMWINDOW == 82 (0000013B6533CFB0) [pid = 10512] [serial = 1026] [outer = 0000000000000000]
[task 2020-06-19T16:54:10.220Z] 16:54:10     INFO - GECKO(10236) | [Parent 10512: Main Thread]: I/DocShellAndDOMWindowLeak ++DOMWINDOW == 83 (0000013B65DEE400) [pid = 10512] [serial = 1027] [outer = 0000013B6533CFB0]
[task 2020-06-19T16:54:10.249Z] 16:54:10     INFO - GECKO(10236) | [Parent 10512, Main Thread] WARNING: IPC message discarded: actor cannot send: file /builds/worker/checkouts/gecko/ipc/glue/ProtocolUtils.cpp, line 470
[task 2020-06-19T16:54:10.250Z] 16:54:10     INFO - GECKO(10236) | [Parent 10512, Main Thread] WARNING: IPC message discarded: actor cannot send: file /builds/[Child 10424: Main Thread]: I/DocShellAndDOMWindowLeak ++DOCSHELL 0000025BEFA73800 == 2 [pid = 10424] [id = {c7e5bb44-5966-4872-810e-19280be6962b}]
[task 2020-06-19T16:54:10.250Z] 16:54:10     INFO - GECKO(10236) | worker/checkouts/gecko/ipc/glue/ProtocolUtils.cpp, l[Child 10424, Main Thread] WARNING: NS_ENSURE_TRUE(browserChrome) faileine 470
[task 2020-06-19T16:54:10.250Z] 16:54:10     INFO - GECKO(10236) | d: file /builds/worke[Parent 1r/checkouts/ge0c5ko1/docshell/base/n2s,DocShell.cpp, li Main Thread] ne 11282
[task 2020-06-19T16:54:10.251Z] 16:54:10     INFO - GECKO(10236) | WARNING: IPC message discarded: actor cannot send: file /builds/worker/checkouts/gecko/ipc/glue/ProtocolUtils[Child 10424: Main Thread]: I/DocShellAndDOMWindowLeak ++DOMWINDOW == 15 (0000025BEFA47090) [pid = 10424] [serial = 283] [outer = 0000000000000000]
[task 2020-06-19T16:54:10.251Z] 16:54:10     INFO - GECKO(10236) | .cpp, line 470