Bug: Intermittent browser/base/content/test/performance/browser_tabdetach.js | Uncaught exception - undefined - timed out after 50 tries.
Status: RESOLVED
Priority: P5
Resolution: INCOMPLETE
Created: 2021-03-27 11:28:28+00:00
Resolved: 2023-07-05 12:01:59+00:00

**Filed by:** malexandru [at] mozilla.com
**Parsed log:** https://treeherder.mozilla.org/logviewer?job_id=334630755&repo=autoland
**Full log:** https://firefox-ci-tc.services.mozilla.com/api/queue/v1/task/HOhErougRUezysvYVUoY_Q/runs/0/artifacts/public/logs/live_backing.log

---
```
[task 2021-03-27T10:08:22.332Z] 10:08:22     INFO - TEST-OK | browser/base/content/test/performance/browser_tabclose_grow.js | took 1187ms
[task 2021-03-27T10:08:22.337Z] 10:08:22     INFO - checking window state
[task 2021-03-27T10:08:22.356Z] 10:08:22     INFO - TEST-START | browser/base/content/test/performance/browser_tabdetach.js
[task 2021-03-27T10:08:31.796Z] 10:08:31     INFO - TEST-INFO | started process screenshot
[task 2021-03-27T10:08:31.861Z] 10:08:31     INFO - TEST-INFO | screenshot: exit 0
[task 2021-03-27T10:08:31.861Z] 10:08:31     INFO - Buffered messages logged at 10:08:22
[task 2021-03-27T10:08:31.862Z] 10:08:31     INFO - Entering test bound test_detach_not_overflowed
[task 2021-03-27T10:08:31.862Z] 10:08:31     INFO - Buffered messages logged at 10:08:23
[task 2021-03-27T10:08:31.862Z] 10:08:31     INFO - TEST-FAIL | browser/base/content/test/performance/browser_tabdetach.js | known reflow at clientX@chrome://browser/content/tabbrowser-tabs.js was encountered 2 times - 
[task 2021-03-27T10:08:31.863Z] 10:08:31     INFO - Full stack:
[task 2021-03-27T10:08:31.863Z] 10:08:31     INFO -   clientX@chrome://browser/content/tabbrowser-tabs.js:497:20
[task 2021-03-27T10:08:31.863Z] 10:08:31     INFO -   on_dragstart@chrome://browser/content/tabbrowser-tabs.js:499:31
[task 2021-03-27T10:08:31.863Z] 10:08:31     INFO -   handleEvent@chrome://browser/content/tabbrowser-tabs.js:1740:29
[task 2021-03-27T10:08:31.863Z] 10:08:31     INFO -   synthesizeMouseAtPoint@chrome://mochikit/content/tests/SimpleTest/EventUtils.js:574:32
[task 2021-03-27T10:08:31.864Z] 10:08:31     INFO -   synthesizeMouse@chrome://mochikit/content/tests/SimpleTest/EventUtils.js:508:10
[task 2021-03-27T10:08:31.864Z] 10:08:31     INFO -   synthesizePlainDragAndDrop@chrome://mochikit/content/tests/SimpleTest/EventUtils.js:3059:22
[task 2021-03-27T10:08:31.864Z] 10:08:31     INFO -   
[task 2021-03-27T10:08:31.864Z] 10:08:31     INFO - Full stack:
[task 2021-03-27T10:08:31.864Z] 10:08:31     INFO -   clientX@chrome://browser/content/tabbrowser-tabs.js:497:20
[task 2021-03-27T10:08:31.865Z] 10:08:31     INFO -   on_dragstart@chrome://browser/content/tabbrowser-tabs.js:499:39
[task 2021-03-27T10:08:31.865Z] 10:08:31     INFO -   handleEvent@chrome://browser/content/tabbrowser-tabs.js:1740:29
[task 2021-03-27T10:08:31.865Z] 10:08:31     INFO -   synthesizeMouseAtPoint@chrome://mochikit/content/tests/SimpleTest/EventUtils.js:574:32
[task 2021-03-27T10:08:31.865Z] 10:08:31     INFO -   synthesizeMouse@chrome://mochikit/content/tests/SimpleTest/EventUtils.js:508:10
[task 2021-03-27T10:08:31.866Z] 10:08:31     INFO -   synthesizePlainDragAndDrop@chrome://mochikit/content/tests/SimpleTest/EventUtils.js:3059:22
[task 2021-03-27T10:08:31.866Z] 10:08:31     INFO -   
[task 2021-03-27T10:08:31.866Z] 10:08:31     INFO - TEST-FAIL | browser/base/content/test/performance/browser_tabdetach.js | known reflow at on_dragstart@chrome://browser/content/tabbrowser-tabs.js was encountered 1 times - 
[task 2021-03-27T10:08:31.866Z] 10:08:31     INFO - Full stack:
[task 2021-03-27T10:08:31.866Z] 10:08:31     INFO -   on_dragstart@chrome://browser/content/tabbrowser-tabs.js:503:9
[task 2021-03-27T10:08:31.866Z] 10:08:31     INFO -   handleEvent@chrome://browser/content/tabbrowser-tabs.js:1740:29
[task 2021-03-27T10:08:31.866Z] 10:08:31     INFO -   synthesizeMouseAtPoint@chrome://mochikit/content/tests/SimpleTest/EventUtils.js:574:32
[task 2021-03-27T10:08:31.866Z] 10:08:31     INFO -   synthesizeMouse@chrome://mochikit/content/tests/SimpleTest/EventUtils.js:508:10
[task 2021-03-27T10:08:31.866Z] 10:08:31     INFO -   synthesizePlainDragAndDrop@chrome://mochikit/content/tests/SimpleTest/EventUtils.js:3059:22
[task 2021-03-27T10:08:31.866Z] 10:08:31     INFO -   
[task 2021-03-27T10:08:31.867Z] 10:08:31     INFO - TEST-PASS | browser/base/content/test/performance/browser_tabdetach.js | 0 unexpected reflows - true == true - 
[task 2021-03-27T10:08:31.867Z] 10:08:31     INFO - comparing 7 frames
[task 2021-03-27T10:08:31.867Z] 10:08:31     INFO - TEST-PASS | browser/base/content/test/performance/browser_tabdetach.js | should have 0 unknown flickering areas - 
[task 2021-03-27T10:08:31.867Z] 10:08:31     INFO - Leaving test bound test_detach_not_overflowed
[task 2021-03-27T10:08:31.867Z] 10:08:31     INFO - Entering test bound test_detach_overflowed
[task 2021-03-27T10:08:31.867Z] 10:08:31     INFO - TEST-PASS | browser/base/content/test/performance/browser_tabdetach.js | Tabstrip needs to be wide enough to accomodate at least 1 more tab without overflowing. - true == true - 
[task 2021-03-27T10:08:31.867Z] 10:08:31     INFO - Buffered messages logged at 10:08:26
[task 2021-03-27T10:08:31.867Z] 10:08:31     INFO - TEST-FAIL | browser/base/content/test/performance/browser_tabdetach.js | known reflow at clientX@chrome://browser/content/tabbrowser-tabs.js was encountered 2 times - 
[task 2021-03-27T10:08:31.867Z] 10:08:31     INFO - Full stack:
[task 2021-03-27T10:08:31.867Z] 10:08:31     INFO -   clientX@chrome://browser/content/tabbrowser-tabs.js:497:20
[task 2021-03-27T10:08:31.867Z] 10:08:31     INFO -   on_dragstart@chrome://browser/content/tabbrowser-tabs.js:499:31
[task 2021-03-27T10:08:31.867Z] 10:08:31     INFO -   handleEvent@chrome://browser/content/tabbrowser-tabs.js:1740:29
[task 2021-03-27T10:08:31.868Z] 10:08:31     INFO -   synthesizeMouseAtPoint@chrome://mochikit/content/tests/SimpleTest/EventUtils.js:574:32
[task 2021-03-27T10:08:31.868Z] 10:08:31     INFO -   synthesizeMouse@chrome://mochikit/content/tests/SimpleTest/EventUtils.js:508:10
[task 2021-03-27T10:08:31.868Z] 10:08:31     INFO -   synthesizePlainDragAndDrop@chrome://mochikit/content/tests/SimpleTest/EventUtils.js:3059:22
[task 2021-03-27T10:08:31.868Z] 10:08:31     INFO -   
[task 2021-03-27T10:08:31.868Z] 10:08:31     INFO - Full stack:
[task 2021-03-27T10:08:31.868Z] 10:08:31     INFO -   clientX@chrome://browser/content/tabbrowser-tabs.js:497:20
[task 2021-03-27T10:08:31.868Z] 10:08:31     INFO -   on_dragstart@chrome://browser/content/tabbrowser-tabs.js:499:39
[task 2021-03-27T10:08:31.868Z] 10:08:31     INFO -   handleEvent@chrome://browser/content/tabbrowser-tabs.js:1740:29
[task 2021-03-27T10:08:31.868Z] 10:08:31     INFO -   synthesizeMouseAtPoint@chrome://mochikit/content/tests/SimpleTest/EventUtils.js:574:32
[task 2021-03-27T10:08:31.868Z] 10:08:31     INFO -   synthesizeMouse@chrome://mochikit/content/tests/SimpleTest/EventUtils.js:508:10
[task 2021-03-27T10:08:31.868Z] 10:08:31     INFO -   synthesizePlainDragAndDrop@chrome://mochikit/content/tests/SimpleTest/EventUtils.js:3059:22
[task 2021-03-27T10:08:31.868Z] 10:08:31     INFO -   
[task 2021-03-27T10:08:31.868Z] 10:08:31     INFO - TEST-FAIL | browser/base/content/test/performance/browser_tabdetach.js | known reflow at on_dragstart@chrome://browser/content/tabbrowser-tabs.js was encountered 1 times - 
[task 2021-03-27T10:08:31.868Z] 10:08:31     INFO - Full stack:
[task 2021-03-27T10:08:31.868Z] 10:08:31     INFO -   on_dragstart@chrome://browser/content/tabbrowser-tabs.js:503:9
[task 2021-03-27T10:08:31.868Z] 10:08:31     INFO -   handleEvent@chrome://browser/content/tabbrowser-tabs.js:1740:29
[task 2021-03-27T10:08:31.868Z] 10:08:31     INFO -   synthesizeMouseAtPoint@chrome://mochikit/content/tests/SimpleTest/EventUtils.js:574:32
[task 2021-03-27T10:08:31.868Z] 10:08:31     INFO -   synthesizeMouse@chrome://mochikit/content/tests/SimpleTest/EventUtils.js:508:10
[task 2021-03-27T10:08:31.868Z] 10:08:31     INFO -   synthesizePlainDragAndDrop@chrome://mochikit/content/tests/SimpleTest/EventUtils.js:3059:22
[task 2021-03-27T10:08:31.868Z] 10:08:31     INFO -   
[task 2021-03-27T10:08:31.869Z] 10:08:31     INFO - TEST-PASS | browser/base/content/test/performance/browser_tabdetach.js | 0 unexpected reflows - true == true - 
[task 2021-03-27T10:08:31.869Z] 10:08:31     INFO - comparing 12 frames
[task 2021-03-27T10:08:31.869Z] 10:08:31     INFO - TEST-PASS | browser/base/content/test/performance/browser_tabdetach.js | should have 0 unknown flickering areas - 
[task 2021-03-27T10:08:31.869Z] 10:08:31     INFO - Buffered messages finished
[task 2021-03-27T10:08:31.869Z] 10:08:31     INFO - TEST-UNEXPECTED-FAIL | browser/base/content/test/performance/browser_tabdetach.js | Uncaught exception - undefined - timed out after 50 tries.
[task 2021-03-27T10:08:31.869Z] 10:08:31     INFO - Leaving test bound test_detach_overflowed
[task 2021-03-27T10:08:31.869Z] 10:08:31     INFO - GECKO(1316) | MEMORY STAT | vsize 2104465MB | vsizeMaxContiguous 67828733MB | residentFast 490MB | heapAllocated 339MB
[task 2021-03-27T10:08:31.869Z] 10:08:31     INFO - TEST-OK | browser/base/content/test/performance/browser_tabdetach.js | took 9478ms```