Filed by: aciure [at] mozilla.com

https://treeherder.mozilla.org/logviewer.html#?job_id=223549167&repo=mozilla-central

https://queue.taskcluster.net/v1/task/dLOIN7cKSQuLPPfmUsKd8w/runs/0/artifacts/public/logs/live_backing.log

[task 2019-01-23T18:15:05.254Z] 18:15:05 INFO - TEST-START | /html/semantics/embedded-content/media-elements/ready-states/autoplay.html
[task 2019-01-23T18:15:15.389Z] 18:15:15 WARNING - Traceback (most recent call last):
[task 2019-01-23T18:15:15.390Z] 18:15:15 WARNING - File "/builds/worker/workspace/build/tests/web-platform/tests/tools/wptrunner/wptrunner/executors/executormarionette.py", line 604, in _run
[task 2019-01-23T18:15:15.391Z] 18:15:15 WARNING - self.result = True, self.func(self.protocol, self.url, self.timeout)
[task 2019-01-23T18:15:15.392Z] 18:15:15 WARNING - File "/builds/worker/workspace/build/tests/web-platform/tests/tools/wptrunner/wptrunner/executors/executormarionette.py", line 712, in do_testharness
[task 2019-01-23T18:15:15.394Z] 18:15:15 WARNING - timeout=10self.timeout_multiplier)
[task 2019-01-23T18:15:15.394Z] 18:15:15 WARNING - File "/builds/worker/workspace/build/tests/web-platform/tests/tools/wptrunner/wptrunner/executors/executormarionette.py", line 226, in get_test_window
[task 2019-01-23T18:15:15.395Z] 18:15:15 WARNING - raise Exception("unable to find test window")
[task 2019-01-23T18:15:15.396Z] 18:15:15 WARNING - Exception: unable to find test window
[task 2019-01-23T18:15:15.397Z] 18:15:15 WARNING -
[task 2019-01-23T18:15:15.398Z] 18:15:15 INFO - TEST-UNEXPECTED-ERROR | /html/semantics/embedded-content/media-elements/ready-states/autoplay.html | unable to find test window
[task 2019-01-23T18:15:15.399Z] 18:15:15 INFO - Traceback (most recent call last):
[task 2019-01-23T18:15:15.399Z] 18:15:15 INFO - File "/builds/worker/workspace/build/tests/web-platform/tests/tools/wptrunner/wptrunner/executors/executormarionette.py", line 604, in _run
[task 2019-01-23T18:15:15.400Z] 18:15:15 INFO - self.result = True, self.func(self.protocol, self.url, self.timeout)
[task 2019-01-23T18:15:15.401Z] 18:15:15 INFO - File "/builds/worker/workspace/build/tests/web-platform/tests/tools/wptrunner/wptrunner/executors/executormarionette.py", line 712, in do_testharness
[task 2019-01-23T18:15:15.401Z] 18:15:15 INFO - timeout=10self.timeout_multiplier)
[task 2019-01-23T18:15:15.402Z] 18:15:15 INFO - File "/builds/worker/workspace/build/tests/web-platform/tests/tools/wptrunner/wptrunner/executors/executormarionette.py", line 226, in get_test_window
[task 2019-01-23T18:15:15.402Z] 18:15:15 INFO - raise Exception("unable to find test window")
[task 2019-01-23T18:15:15.403Z] 18:15:15 INFO - Exception: unable to find test window
[task 2019-01-23T18:15:15.403Z] 18:15:15 INFO - TEST-INFO took 10139ms
[task 2019-01-23T18:15:15.420Z] 18:15:15 INFO - PID 31559 | 1548267315411 Marionette INFO Stopped listening on port 2828
[task 2019-01-23T18:15:25.438Z] 18:15:25 INFO - PID 31559 | WARNING: At least one completion condition is taking too long to complete. Conditions: [{"name":"SessionStore: flushing all windows","state":{"total":1,"current":0},"filename":"resource:///modules/sessionstore/SessionStore.jsm","lineNumber":1610,"stack":["resource:///modules/sessionstore/SessionStore.jsm:ssi_onQuitApplicationGranted:1610","resource:///modules/sessionstore/SessionStore.jsm:ssi_observe:777","chrome://marionette/content/driver.js:GeckoDriver.prototype.quit:3349"]}] Barrier: quit-application-granted
[task 2019-01-23T18:16:26.427Z] 18:16:26 INFO - Browser exited with return code -15
[task 2019-01-23T18:16:26.427Z] 18:16:26 INFO - PROCESS LEAKS None
[task 2019-01-23T18:16:26.430Z] 18:16:26 INFO - Closing logging queue
[task 2019-01-23T18:16:26.431Z] 18:16:26 INFO - queue closed

:drno , there are a few different tests that fail with "unable to find test window" after "Exception: unable to find test window".
Could you please take a look?

James could this have started from Bug 1519862 ? can you please take a look?

https://treeherder.mozilla.org/#/jobs?repo=mozilla-central&selectedJob=223549167&searchStr=linux%2Cx64%2Cquantumrender%2Copt%2Cweb%2Cplatform%2Ctests%2Cwith%2Ce10s%2Ctest-linux64-qr%2Fopt-web-platform-tests-e10s-1%2Cw-e10s%28wpt1%29&tochange=4f1ff0e34dd59539c8c0d133ecdff5660ec4e263&fromchange=44369796f148630ff496be99f77a5eeea41c7d23

There are 22 total failures in the last 7 days: https://treeherder.mozilla.org/intermittent-failures.html#/bugdetails?startday=2019-01-29&endday=2019-02-05&tree=trunk&bug=1522333

There seem to be no other occurrences since the 3rd of February.

The problem here is that some tests are broken and try to do unsupported things like navigate the test window, which leads to the kind of error you see here. Those tests need to be fixed.

This turned into a perma-fail: https://treeherder.mozilla.org/#/jobs?repo=mozilla-central&resultStatus=pending%2Crunning%2Csuccess%2Ctestfailed%2Cbusted%2Cexception&searchStr=b0091322fcb1efbade63dfa09d14aa764fd4b804&fromchange=adeaa48edc50404d3c77a2faaf496ac89711b8f6&tochange=408f6c0f98146da1f540d5b6759e4d9a787db8ab

James, could this be caused by Bug1605340?

I just had this locally as well with an IndexedDB test:

ERROR /IndexedDB/idb-explicit-commit.any.worker.html - unable to find test window
Traceback (most recent call last):
  File "/home/simon/work/mozilla-unified/testing/web-platform/tests/tools/wptrunner/wptrunner/executors/executormarionette.py", line 642, in run_func
    self.result = True, self.func(self.protocol, self.url, self.timeout)
  File "/home/simon/work/mozilla-unified/testing/web-platform/tests/tools/wptrunner/wptrunner/executors/executormarionette.py", line 747, in do_testharness
    timeout=10*self.timeout_multiplier)
  File "/home/simon/work/mozilla-unified/testing/web-platform/tests/tools/wptrunner/wptrunner/executors/executormarionette.py", line 233, in get_test_window
    raise Exception("unable to find test window")
Exception: unable to find test window

Changing component since this doesn't appear to be specific to a particular test.

There are 40 total failures in the last 7 days on windows10-64-ccov opt in the last 7 days.

Recent failure log: https://treeherder.mozilla.org/logviewer.html#/jobs?job_id=285791906&repo=mozilla-central&lineNumber=8188

[task 2020-01-21T17:02:35.931Z] 17:02:35 INFO - TEST-START | /offscreen-canvas/fill-and-stroke-styles/2d.gradient.radial.cone.front.html
[task 2020-01-21T17:02:35.936Z] 17:02:35 INFO - Closing window 647
[task 2020-01-21T17:02:36.000Z] 17:02:36 INFO - PID 2964 | ###!!! [Parent][RunMessage] Error: Channel closing: too late to send/recv, messages will be lost
[task 2020-01-21T17:02:36.510Z] 17:02:36 INFO - .
[task 2020-01-21T17:02:36.510Z] 17:02:36 INFO - TEST-OK | /offscreen-canvas/fill-and-stroke-styles/2d.gradient.radial.cone.front.html | took 580ms
[task 2020-01-21T17:02:36.510Z] 17:02:36 INFO - TEST-START | /offscreen-canvas/fill-and-stroke-styles/2d.gradient.radial.cone.front.worker.html
[task 2020-01-21T17:02:36.519Z] 17:02:36 INFO - Closing window 649
[task 2020-01-21T17:02:36.579Z] 17:02:36 INFO - PID 2964 | ###!!! [Parent][RunMessage] Error: Channel closing: too late to send/recv, messages will be lost
[task 2020-01-21T17:02:37.194Z] 17:02:37 INFO - .
[task 2020-01-21T17:02:37.194Z] 17:02:37 INFO - TEST-OK | /offscreen-canvas/fill-and-stroke-styles/2d.gradient.radial.cone.front.worker.html | took 683ms
[task 2020-01-21T17:02:37.194Z] 17:02:37 INFO - TEST-START | /offscreen-canvas/fill-and-stroke-styles/2d.gradient.radial.cone.shape1.html
[task 2020-01-21T17:02:37.204Z] 17:02:37 INFO - Closing window 651
[task 2020-01-21T17:02:37.264Z] 17:02:37 INFO - PID 2964 | ###!!! [Parent][RunMessage] Error: Channel closing: too late to send/recv, messages will be lost
[task 2020-01-21T17:02:37.827Z] 17:02:37 INFO - .
[task 2020-01-21T17:02:37.827Z] 17:02:37 INFO - TEST-OK | /offscreen-canvas/fill-and-stroke-styles/2d.gradient.radial.cone.shape1.html | took 632ms
[task 2020-01-21T17:02:37.827Z] 17:02:37 INFO - TEST-START | /offscreen-canvas/fill-and-stroke-styles/2d.gradient.radial.cone.shape1.worker.html
[task 2020-01-21T17:02:37.846Z] 17:02:37 INFO - Closing window 653
[task 2020-01-21T17:02:37.904Z] 17:02:37 INFO - PID 2964 | ###!!! [Parent][RunMessage] Error: Channel closing: too late to send/recv, messages will be lost
[task 2020-01-21T17:02:38.817Z] 17:02:38 INFO - .
[task 2020-01-21T17:02:38.817Z] 17:02:38 INFO - TEST-OK | /offscreen-canvas/fill-and-stroke-styles/2d.gradient.radial.cone.shape1.worker.html | took 989ms
[task 2020-01-21T17:02:38.817Z] 17:02:38 INFO - TEST-START | /offscreen-canvas/fill-and-stroke-styles/2d.gradient.radial.cone.shape2.html
[task 2020-01-21T17:02:38.822Z] 17:02:38 INFO - Closing window 655
[task 2020-01-21T17:02:38.901Z] 17:02:38 INFO - PID 2964 | ###!!! [Parent][RunMessage] Error: Channel closing: too late to send/recv, messages will be lost
[task 2020-01-21T17:02:39.653Z] 17:02:39 INFO - .
[task 2020-01-21T17:02:39.653Z] 17:02:39 INFO - TEST-OK | /offscreen-canvas/fill-and-stroke-styles/2d.gradient.radial.cone.shape2.html | took 836ms
[task 2020-01-21T17:02:39.653Z] 17:02:39 INFO - TEST-START | /offscreen-canvas/fill-and-stroke-styles/2d.gradient.radial.cone.shape2.worker.html
[task 2020-01-21T17:02:39.657Z] 17:02:39 INFO - Closing window 657
[task 2020-01-21T17:02:39.718Z] 17:02:39 INFO - PID 2964 | ###!!! [Parent][RunMessage] Error: Channel closing: too late to send/recv, messages will be lost
[task 2020-01-21T17:02:40.840Z] 17:02:40 INFO - .
[task 2020-01-21T17:02:40.840Z] 17:02:40 INFO - TEST-OK | /offscreen-canvas/fill-and-stroke-styles/2d.gradient.radial.cone.shape2.worker.html | took 1187ms
[task 2020-01-21T17:02:40.840Z] 17:02:40 INFO - TEST-START | /offscreen-canvas/fill-and-stroke-styles/2d.gradient.radial.cone.top.html
[task 2020-01-21T17:02:40.850Z] 17:02:40 INFO - Closing window 659
[task 2020-01-21T17:02:40.909Z] 17:02:40 INFO - PID 2964 | ###!!! [Parent][RunMessage] Error: Channel closing: too late to send/recv, messages will be lost
[task 2020-01-21T17:02:41.378Z] 17:02:41 INFO - .
[task 2020-01-21T17:02:41.378Z] 17:02:41 INFO - TEST-OK | /offscreen-canvas/fill-and-stroke-styles/2d.gradient.radial.cone.top.html | took 534ms
[task 2020-01-21T17:02:41.378Z] 17:02:41 INFO - TEST-START | /offscreen-canvas/fill-and-stroke-styles/2d.gradient.radial.cone.top.worker.html
[task 2020-01-21T17:02:41.378Z] 17:02:41 INFO - Closing window 661
[task 2020-01-21T17:02:41.439Z] 17:02:41 INFO - PID 2964 | ###!!! [Parent][RunMessage] Error: Channel closing: too late to send/recv, messages will be lost
[task 2020-01-21T17:02:42.207Z] 17:02:42 INFO - .
[task 2020-01-21T17:02:42.207Z] 17:02:42 INFO - TEST-OK | /offscreen-canvas/fill-and-stroke-styles/2d.gradient.radial.cone.top.worker.html | took 833ms
[task 2020-01-21T17:02:42.207Z] 17:02:42 INFO - TEST-START | /offscreen-canvas/fill-and-stroke-styles/2d.gradient.radial.equal.html
[task 2020-01-21T17:02:42.216Z] 17:02:42 INFO - Closing window 663
[task 2020-01-21T17:02:42.276Z] 17:02:42 INFO - PID 2964 | ###!!! [Parent][RunMessage] Error: Channel closing: too late to send/recv, messages will be lost
[task 2020-01-21T17:02:42.786Z] 17:02:42 INFO - .
[task 2020-01-21T17:02:42.786Z] 17:02:42 INFO - TEST-OK | /offscreen-canvas/fill-and-stroke-styles/2d.gradient.radial.equal.html | took 579ms
[task 2020-01-21T17:02:42.786Z] 17:02:42 INFO - TEST-START | /offscreen-canvas/fill-and-stroke-styles/2d.gradient.radial.equal.worker.html
[task 2020-01-21T17:02:42.795Z] 17:02:42 INFO - Closing window 665
[task 2020-01-21T17:02:42.854Z] 17:02:42 INFO - PID 2964 | ###!!! [Parent][RunMessage] Error: Channel closing: too late to send/recv, messages will be lost
[task 2020-01-21T17:02:44.032Z] 17:02:44 INFO - .
[task 2020-01-21T17:02:44.032Z] 17:02:44 INFO - TEST-OK | /offscreen-canvas/fill-and-stroke-styles/2d.gradient.radial.equal.worker.html | took 1243ms
[task 2020-01-21T17:02:44.032Z] 17:02:44 INFO - TEST-START | /offscreen-canvas/fill-and-stroke-styles/2d.gradient.radial.inside1.html
[task 2020-01-21T17:02:44.037Z] 17:02:44 INFO - Closing window 667
[task 2020-01-21T17:02:44.095Z] 17:02:44 INFO - PID 2964 | ###!!! [Parent][RunMessage] Error: Channel closing: too late to send/recv, messages will be lost
[task 2020-01-21T17:02:44.613Z] 17:02:44 INFO - .
[task 2020-01-21T17:02:44.613Z] 17:02:44 INFO - TEST-OK | /offscreen-canvas/fill-and-stroke-styles/2d.gradient.radial.inside1.html | took 582ms
[task 2020-01-21T17:02:44.613Z] 17:02:44 INFO - TEST-START | /offscreen-canvas/fill-and-stroke-styles/2d.gradient.radial.inside1.worker.html
[task 2020-01-21T17:02:44.618Z] 17:02:44 INFO - Closing window 669
[task 2020-01-21T17:02:44.678Z] 17:02:44 INFO - PID 2964 | ###!!! [Parent][RunMessage] Error: Channel closing: too late to send/recv, messages will be lost
[task 2020-01-21T17:02:45.448Z] 17:02:45 INFO - .
[task 2020-01-21T17:02:45.448Z] 17:02:45 INFO - TEST-OK | /offscreen-canvas/fill-and-stroke-styles/2d.gradient.radial.inside1.worker.html | took 835ms
[task 2020-01-21T17:02:45.448Z] 17:02:45 INFO - TEST-START | /offscreen-canvas/fill-and-stroke-styles/2d.gradient.radial.inside2.html
[task 2020-01-21T17:02:45.453Z] 17:02:45 INFO - Closing window 671
[task 2020-01-21T17:02:45.514Z] 17:02:45 INFO - PID 2964 | ###!!! [Parent][RunMessage] Error: Channel closing: too late to send/recv, messages will be lost
[task 2020-01-21T17:02:46.029Z] 17:02:46 INFO - .
[task 2020-01-21T17:02:46.029Z] 17:02:46 INFO - TEST-OK | /offscreen-canvas/fill-and-stroke-styles/2d.gradient.radial.inside2.html | took 581ms
[task 2020-01-21T17:02:46.029Z] 17:02:46 INFO - TEST-START | /offscreen-canvas/fill-and-stroke-styles/2d.gradient.radial.inside2.worker.html
[task 2020-01-21T17:02:46.039Z] 17:02:46 INFO - Closing window 673
[task 2020-01-21T17:02:46.099Z] 17:02:46 INFO - PID 2964 | ###!!! [Parent][RunMessage] Error: Channel closing: too late to send/recv, messages will be lost
[task 2020-01-21T17:02:46.714Z] 17:02:46 INFO - .
[task 2020-01-21T17:02:46.714Z] 17:02:46 INFO - TEST-OK | /offscreen-canvas/fill-and-stroke-styles/2d.gradient.radial.inside2.worker.html | took 684ms
[task 2020-01-21T17:02:46.714Z] 17:02:46 INFO - TEST-START | /offscreen-canvas/fill-and-stroke-styles/2d.gradient.radial.inside3.html
[task 2020-01-21T17:02:46.719Z] 17:02:46 INFO - Closing window 675
[task 2020-01-21T17:02:46.780Z] 17:02:46 INFO - PID 2964 | ###!!! [Parent][RunMessage] Error: Channel closing: too late to send/recv, messages will be lost
[task 2020-01-21T17:02:47.342Z] 17:02:47 INFO - .
[task 2020-01-21T17:02:47.343Z] 17:02:47 INFO - TEST-OK | /offscreen-canvas/fill-and-stroke-styles/2d.gradient.radial.inside3.html | took 630ms
[task 2020-01-21T17:02:47.343Z] 17:02:47 INFO - TEST-START | /offscreen-canvas/fill-and-stroke-styles/2d.gradient.radial.inside3.worker.html
[task 2020-01-21T17:02:47.353Z] 17:02:47 INFO - Closing window 677
[task 2020-01-21T17:02:47.413Z] 17:02:47 INFO - PID 2964 | ###!!! [Parent][RunMessage] Error: Channel closing: too late to send/recv, messages will be lost
[task 2020-01-21T17:02:48.280Z] 17:02:48 INFO - .
[task 2020-01-21T17:02:48.280Z] 17:02:48 INFO - TEST-OK | /offscreen-canvas/fill-and-stroke-styles/2d.gradient.radial.inside3.worker.html | took 934ms
[task 2020-01-21T17:02:48.280Z] 17:02:48 INFO - TEST-START | /offscreen-canvas/fill-and-stroke-styles/2d.gradient.radial.negative.html
[task 2020-01-21T17:02:48.284Z] 17:02:48 INFO - Closing window 679
[task 2020-01-21T17:02:48.349Z] 17:02:48 INFO - PID 2964 | ###!!! [Parent][RunMessage] Error: Channel closing: too late to send/recv, messages will be lost
[task 2020-01-21T17:02:49.321Z] 17:02:49 INFO - .
[task 2020-01-21T17:02:49.321Z] 17:02:49 INFO - TEST-OK | /offscreen-canvas/fill-and-stroke-styles/2d.gradient.radial.negative.html | took 1036ms
[task 2020-01-21T17:02:49.321Z] 17:02:49 INFO - TEST-START | /offscreen-canvas/fill-and-stroke-styles/2d.gradient.radial.negative.worker.html
[task 2020-01-21T17:02:49.321Z] 17:02:49 INFO - Closing window 681
[task 2020-01-21T17:02:49.382Z] 17:02:49 INFO - PID 2964 | ###!!! [Parent][RunMessage] Error: Channel closing: too late to send/recv, messages will be lost
[task 2020-01-21T17:02:49.997Z] 17:02:49 INFO - .
[task 2020-01-21T17:02:49.997Z] 17:02:49 INFO - TEST-OK | /offscreen-canvas/fill-and-stroke-styles/2d.gradient.radial.negative.worker.html | took 680ms
[task 2020-01-21T17:02:49.997Z] 17:02:49 INFO - TEST-START | /offscreen-canvas/fill-and-stroke-styles/2d.gradient.radial.nonfinite.html
[task 2020-01-21T17:02:50.001Z] 17:02:50 INFO - Closing window 683
[task 2020-01-21T17:02:50.059Z] 17:02:50 INFO - PID 2964 | ###!!! [Parent][RunMessage] Error: Channel closing: too late to send/recv, messages will be lost
[task 2020-01-21T17:02:50.783Z] 17:02:50 INFO - .
[task 2020-01-21T17:02:50.783Z] 17:02:50 INFO - TEST-OK | /offscreen-canvas/fill-and-stroke-styles/2d.gradient.radial.nonfinite.html | took 787ms
[task 2020-01-21T17:02:50.783Z] 17:02:50 INFO - TEST-START | /offscreen-canvas/fill-and-stroke-styles/2d.gradient.radial.nonfinite.worker.html
[task 2020-01-21T17:02:50.793Z] 17:02:50 INFO - Closing window 685
[task 2020-01-21T17:02:50.851Z] 17:02:50 INFO - PID 2964 | ###!!! [Parent][RunMessage] Error: Channel closing: too late to send/recv, messages will be lost
[task 2020-01-21T17:02:51.878Z] 17:02:51 INFO - .
[task 2020-01-21T17:02:51.878Z] 17:02:51 INFO - TEST-OK | /offscreen-canvas/fill-and-stroke-styles/2d.gradient.radial.nonfinite.worker.html | took 1093ms
[task 2020-01-21T17:02:51.878Z] 17:02:51 INFO - TEST-START | /offscreen-canvas/fill-and-stroke-styles/2d.gradient.radial.outside1.html
[task 2020-01-21T17:02:51.883Z] 17:02:51 INFO - Closing window 687
[task 2020-01-21T17:02:51.947Z] 17:02:51 INFO - PID 2964 | ###!!! [Parent][RunMessage] Error: Channel closing: too late to send/recv, messages will be lost
[task 2020-01-21T17:02:52.457Z] 17:02:52 INFO - .
[task 2020-01-21T17:02:52.457Z] 17:02:52 INFO - TEST-OK | /offscreen-canvas/fill-and-stroke-styles/2d.gradient.radial.outside1.html | took 580ms
[task 2020-01-21T17:02:52.458Z] 17:02:52 INFO - TEST-START | /offscreen-canvas/fill-and-stroke-styles/2d.gradient.radial.outside1.worker.html
[task 2020-01-21T17:02:52.468Z] 17:02:52 INFO - Closing window 689
[task 2020-01-21T17:02:52.526Z] 17:02:52 INFO - PID 2964 | ###!!! [Parent][RunMessage] Error: Channel closing: too late to send/recv, messages will be lost
[task 2020-01-21T17:02:54.014Z] 17:02:54 INFO - .
[task 2020-01-21T17:02:54.014Z] 17:02:54 INFO - TEST-OK | /offscreen-canvas/fill-and-stroke-styles/2d.gradient.radial.outside1.worker.html | took 1556ms
[task 2020-01-21T17:02:54.014Z] 17:02:54 INFO - TEST-START | /offscreen-canvas/fill-and-stroke-styles/2d.gradient.radial.outside2.html
[task 2020-01-21T17:02:54.023Z] 17:02:54 INFO - Closing window 691
[task 2020-01-21T17:02:54.112Z] 17:02:54 INFO - PID 2964 | ###!!! [Parent][RunMessage] Error: Channel closing: too late to send/recv, messages will be lost
[task 2020-01-21T17:03:04.209Z] 17:03:04 WARNING - Traceback (most recent call last):
[task 2020-01-21T17:03:04.209Z] 17:03:04 WARNING - File "Z:\task_1579623004\build\tests\web-platform\tests\tools\wptrunner\wptrunner\executors\executormarionette.py", line 642, in run_func
[task 2020-01-21T17:03:04.209Z] 17:03:04 WARNING - self.result = True, self.func(self.protocol, self.url, self.timeout)
[task 2020-01-21T17:03:04.209Z] 17:03:04 WARNING - File "Z:\task_1579623004\build\tests\web-platform\tests\tools\wptrunner\wptrunner\executors\executormarionette.py", line 747, in do_testharness
[task 2020-01-21T17:03:04.209Z] 17:03:04 WARNING - timeout=10self.timeout_multiplier)
[task 2020-01-21T17:03:04.209Z] 17:03:04 WARNING - File "Z:\task_1579623004\build\tests\web-platform\tests\tools\wptrunner\wptrunner\executors\executormarionette.py", line 233, in get_test_window
[task 2020-01-21T17:03:04.209Z] 17:03:04 WARNING - raise Exception("unable to find test window")
[task 2020-01-21T17:03:04.209Z] 17:03:04 WARNING - Exception: unable to find test window
[task 2020-01-21T17:03:04.209Z] 17:03:04 WARNING -
[task 2020-01-21T17:03:04.248Z] 17:03:04 INFO - TEST-UNEXPECTED-ERROR | /offscreen-canvas/fill-and-stroke-styles/2d.gradient.radial.outside2.html | unable to find test window
[task 2020-01-21T17:03:04.248Z] 17:03:04 INFO - Traceback (most recent call last):
[task 2020-01-21T17:03:04.248Z] 17:03:04 INFO - File "Z:\task_1579623004\build\tests\web-platform\tests\tools\wptrunner\wptrunner\executors\executormarionette.py", line 642, in run_func
[task 2020-01-21T17:03:04.248Z] 17:03:04 INFO - self.result = True, self.func(self.protocol, self.url, self.timeout)
[task 2020-01-21T17:03:04.248Z] 17:03:04 INFO - File "Z:\task_1579623004\build\tests\web-platform\tests\tools\wptrunner\wptrunner\executors\executormarionette.py", line 747, in do_testharness
[task 2020-01-21T17:03:04.248Z] 17:03:04 INFO - timeout=10self.timeout_multiplier)
[task 2020-01-21T17:03:04.248Z] 17:03:04 INFO - File "Z:\task_1579623004\build\tests\web-platform\tests\tools\wptrunner\wptrunner\executors\executormarionette.py", line 233, in get_test_window
[task 2020-01-21T17:03:04.248Z] 17:03:04 INFO - raise Exception("unable to find test window")
[task 2020-01-21T17:03:04.248Z] 17:03:04 INFO - Exception: unable to find test window
[task 2020-01-21T17:03:04.248Z] 17:03:04 INFO - TEST-INFO took 10229ms
[task 2020-01-21T17:03:04.270Z] 17:03:04 INFO - PID 2964 | 1579626184265 Marionette INFO Stopped listening on port 50072
[task 2020-01-21T17:03:04.420Z] 17:03:04 INFO - PID 2964 | ###!!! [Parent][RunMessage] Error: Channel closing: too late to send/recv, messages will be lost
[task 2020-01-21T17:03:14.312Z] 17:03:14 INFO - PID 2964 | WARNING: At least one completion condition is taking too long to complete. Conditions: [{"name":"SessionStore: flushing all windows","state":{"total":1,"current":0},"filename":"resource:///modules/sessionstore/SessionStore.jsm","lineNumber":1824,"stack":["resource:///modules/sessionstore/SessionStore.jsm:ssi_onQuitApplicationGranted:1824","resource:///modules/sessionstore/SessionStore.jsm:ssi_observe:872","chrome://marionette/content/driver.js:GeckoDriver.prototype.quit:3502","chrome://marionette/content/server.js:despatch:305","chrome://marionette/content/server.js:execute:275","chrome://marionette/content/server.js:onPacket/<:248","chrome://marionette/content/server.js:onPacket:249","chrome://marionette/content/transport.js:_onJSONObjectReady/<:501"]}] Barrier: quit-application-granted
[task 2020-01-21T17:03:55.403Z] 17:03:55 INFO - PID 2964 | ###!!! [Parent][RunMessage] Error: Channel closing: too late to send/recv, messages will be lost
[task 2020-01-21T17:03:55.408Z] 17:03:55 INFO - PID 2964 | ###!!! [Parent][RunMessage] Error: Channel closing: too late to send/recv, messages will be lost

James can you please take a look?

James, looked through a bunch of logs and noticed that the windows ccov failures all are failing on different tests from /offscreen-canvas/fill-and-stroke-styles/ and this started after https://hg.mozilla.org/mozilla-central/rev/8e91ec1ac952d4056e6cfb5626ac1454f5837c45 got into central.

There are only 2 Android failures so far, both on /mediacapture-record/MediaRecorder-peerconnection.https.html after https://hg.mozilla.org/mozilla-central/rev/2d1e71521d7152295dab923fbde3360657d14878 was landed.

Could you take a look over this or redirect it to someone as it has 95 failures since jan 10th: https://treeherder.mozilla.org/intermittent-failures.html#/bugdetails?startday=2019-12-28&endday=2020-01-27&tree=trunk&bug=1522333 ? Thank you.

(In reply to Cosmin Sabou [:CosminS] from comment #43)

James, looked through a bunch of logs and noticed that the windows ccov failures all are failing on different tests from /offscreen-canvas/fill-and-stroke-styles/ and this started after https://hg.mozilla.org/mozilla-central/rev/8e91ec1ac952d4056e6cfb5626ac1454f5837c45 got into central.

There are only 2 Android failures so far, both on /mediacapture-record/MediaRecorder-peerconnection.https.html after https://hg.mozilla.org/mozilla-central/rev/2d1e71521d7152295dab923fbde3360657d14878 was landed.

Could you take a look over this or redirect it to someone as it has 95 failures since jan 10th: https://treeherder.mozilla.org/intermittent-failures.html#/bugdetails?startday=2019-12-28&endday=2020-01-27&tree=trunk&bug=1522333 ? Thank you.

Previously, these tests were malformed and essentially not running. Now they are, and could be exposing bugs in Firefox? Last time I tried enabling offscreen-canvas in Firefox and testing it, it would just crash immediately. I also didn't think there was any 2d OffscreenCanvas support in Firefox at all(?) Could be the issue is with ImageBitmap, which these tests now pretty heavily rely on.

My guess is that we're really slow to open the test window in ccov builds for some reason; there's currently a polling loop with a fixed timeout. There's a patch elsewhere to increase the timeout multiplier for ccov opt builds, so that might help, and I should try ressurecting the patch to make marionette handle the new window and avoid having a poll loop at least in the test code.

James, Chris any chance to tackle this in the future wpt-sync?
This has 161 total failures in the last 30 days, most of them on windows ccov and a few on android. https://treeherder.mozilla.org/intermittent-failures.html#/bugdetails?startday=2020-01-08&endday=2020-02-07&tree=trunk&bug=1522333

(In reply to Cosmin Sabou [:CosminS] from comment #51)

James, Chris any chance to tackle this in the future wpt-sync?
This has 161 total failures in the last 30 days, most of them on windows ccov and a few on android. https://treeherder.mozilla.org/intermittent-failures.html#/bugdetails?startday=2020-01-08&endday=2020-02-07&tree=trunk&bug=1522333

As far as I'm aware, this is a Firefox bug? Let me know if there's something that needs to be fixed in the tests themselves and I'll take a look, but I don't currently have time to work on Gecko.

James, going back to comment 45, do you think you can have a fix for these failures? Or might this need a test folder disabling?
Looked through this week logs and found the following:
Android failures are all on

• /mediacapture-record/MediaRecorder-peerconnection.https.html.

linux1804-64-ccov:

• /mixed-content/gen/top.meta/opt-in/picture-tag/cross-http.no-redirect.https.html
• offscreen-canvas/fill-and-stroke-styles/2d.gradient.radial.outside3.worker.html
• /css/css-flexbox/animation/flex-basis-composition.html
• /css/filter-effects/animation/backdrop-filter-interpolation-001.html
• html/dom/documents/resource-metadata-management/document-compatmode-01.html
• /html/semantics/embedded-content/media-elements/interfaces/HTMLElement/HTMLMediaElement/addTextTrack.html
• /referrer-policy/gen/srcdoc-inherit.meta/no-referrer-when-downgrade/xhr/cross-http.keep-origin.http.html
• /referrer-policy/gen/srcdoc-inherit.http-rp/no-referrer-when-downgrade/img-tag/cross-http.keep-origin.http.html

windows10-64-ccov - just a part of them:

• /offscreen-canvas/fill-and-stroke-styles/2d.gradient.radial.cone.bottom.worker.html
• /offscreen-canvas/fill-and-stroke-styles/2d.pattern.basic.canvas.html
• /offscreen-canvas/fill-and-stroke-styles/2d.gradient.radial.outside1.worker.html
• /offscreen-canvas/fill-and-stroke-styles/2d.pattern.paint.repeaty.outside.worker.html
• /offscreen-canvas/fill-and-stroke-styles/2d.gradient.radial.outside2.html
• /offscreen-canvas/fill-and-stroke-styles/2d.gradient.radial.outside3.html x2
• /offscreen-canvas/fill-and-stroke-styles/2d.pattern.basic.image.worker.html
• /offscreen-canvas/fill-and-stroke-styles/2d.pattern.image.undefined.worker.html
• /offscreen-canvas/fill-and-stroke-styles/2d.pattern.paint.norepeat.coord1.html
• /offscreen-canvas/fill-and-stroke-styles/2d.gradient.radial.outside2.worker.html
• /offscreen-canvas/fill-and-stroke-styles/2d.gradient.radial.inside1.html

I don't think this problem is specific to any particular tests. The failing function is called from do_testharness at https://searchfox.org/mozilla-central/rev/cc0f9906505d0ffa0d3a29a80142379e21cb5fb2/testing/web-platform/tests/tools/wptrunner/wptrunner/executors/executormarionette.py#745 (and similar calls exist for the other executors), which is executed before the actual test case is run. It might be a side-effect of earlier test cases that were executed. It might just be that the specified timeout is too short under certain circumstances?

https://hg.mozilla.org/mozilla-central/rev/67d6bbcfc46d

https://hg.mozilla.org/mozilla-central/rev/6927a72a187f

There are 56 total failures in the last 7 days on win ccov

Recent failure log: https://treeherder.mozilla.org/logviewer.html#/jobs?job_id=290857246&repo=mozilla-central&lineNumber=8579

[task 2020-02-27T23:48:11.286Z] 23:48:11 INFO - TEST-START | /referrer-policy/4K/gen/top.meta/unsafe-url/xhr/same-https.keep-origin.http.html
[task 2020-02-27T23:48:11.291Z] 23:48:11 INFO - Closing window 924
[task 2020-02-27T23:48:11.351Z] 23:48:11 INFO - PID 10416 | ###!!! [Parent][RunMessage] Error: Channel closing: too late to send/recv, messages will be lost
[task 2020-02-27T23:48:31.521Z] 23:48:31 WARNING - Traceback (most recent call last):
[task 2020-02-27T23:48:31.521Z] 23:48:31 WARNING - File "Z:\task_1582843161\build\tests\web-platform\tests\tools\wptrunner\wptrunner\executors\executormarionette.py", line 642, in run_func
[task 2020-02-27T23:48:31.521Z] 23:48:31 WARNING - self.result = True, self.func(self.protocol, self.url, self.timeout)
[task 2020-02-27T23:48:31.521Z] 23:48:31 WARNING - File "Z:\task_1582843161\build\tests\web-platform\tests\tools\wptrunner\wptrunner\executors\executormarionette.py", line 747, in do_testharness
[task 2020-02-27T23:48:31.521Z] 23:48:31 WARNING - timeout=10self.timeout_multiplier)
[task 2020-02-27T23:48:31.521Z] 23:48:31 WARNING - File "Z:\task_1582843161\build\tests\web-platform\tests\tools\wptrunner\wptrunner\executors\executormarionette.py", line 234, in get_test_window
[task 2020-02-27T23:48:31.521Z] 23:48:31 WARNING - raise Exception("unable to find test window")
[task 2020-02-27T23:48:31.521Z] 23:48:31 WARNING - Exception: unable to find test window
[task 2020-02-27T23:48:31.521Z] 23:48:31 WARNING -
[task 2020-02-27T23:48:31.522Z] 23:48:31 INFO - TEST-UNEXPECTED-ERROR | /referrer-policy/4K/gen/top.meta/unsafe-url/xhr/same-https.keep-origin.http.html | unable to find test window
[task 2020-02-27T23:48:31.522Z] 23:48:31 INFO - Traceback (most recent call last):
[task 2020-02-27T23:48:31.522Z] 23:48:31 INFO - File "Z:\task_1582843161\build\tests\web-platform\tests\tools\wptrunner\wptrunner\executors\executormarionette.py", line 642, in run_func
[task 2020-02-27T23:48:31.522Z] 23:48:31 INFO - self.result = True, self.func(self.protocol, self.url, self.timeout)
[task 2020-02-27T23:48:31.522Z] 23:48:31 INFO - File "Z:\task_1582843161\build\tests\web-platform\tests\tools\wptrunner\wptrunner\executors\executormarionette.py", line 747, in do_testharness
[task 2020-02-27T23:48:31.522Z] 23:48:31 INFO - timeout=10self.timeout_multiplier)
[task 2020-02-27T23:48:31.522Z] 23:48:31 INFO - File "Z:\task_1582843161\build\tests\web-platform\tests\tools\wptrunner\wptrunner\executors\executormarionette.py", line 234, in get_test_window
[task 2020-02-27T23:48:31.522Z] 23:48:31 INFO - raise Exception("unable to find test window")
[task 2020-02-27T23:48:31.522Z] 23:48:31 INFO - Exception: unable to find test window
[task 2020-02-27T23:48:31.522Z] 23:48:31 INFO - TEST-INFO took 20238ms
[task 2020-02-27T23:48:31.552Z] 23:48:31 INFO - PID 10416 | 1582847311544 Marionette INFO Stopped listening on port 50100
[task 2020-02-27T23:48:31.706Z] 23:48:31 INFO - PID 10416 | ###!!! [Parent][RunMessage] Error: Channel closing: too late to send/recv, messages will be lost
[task 2020-02-27T23:48:41.589Z] 23:48:41 INFO - PID 10416 | WARNING: At least one completion condition is taking too long to complete. Conditions: [{"name":"SessionStore: flushing all windows","state":{"total":1,"current":0},"filename":"resource:///modules/sessionstore/SessionStore.jsm","lineNumber":1823,"stack":["resource:///modules/sessionstore/SessionStore.jsm:ssi_onQuitApplicationGranted:1823","resource:///modules/sessionstore/SessionStore.jsm:ssi_observe:871","chrome://marionette/content/driver.js:GeckoDriver.prototype.quit:3514","chrome://marionette/content/server.js:despatch:305","chrome://marionette/content/server.js:execute:275","chrome://marionette/content/server.js:onPacket/<:248","chrome://marionette/content/server.js:onPacket:249","chrome://marionette/content/transport.js:_onJSONObjectReady/<:501"]}] Barrier: quit-application-granted
[task 2020-02-27T23:49:22.683Z] 23:49:22 INFO - PID 10416 | ###!!! [Parent][RunMessage] Error: Channel closing: too late to send/recv, messages will be lost
[task 2020-02-27T23:49:37.592Z] 23:49:37 INFO - PID 10416 | console.error: (new Error("SessionFile is closed", "resource:///modules/sessionstore/SessionFile.jsm", 433))
[task 2020-02-27T23:49:43.620Z] 23:49:43 INFO - Browser exited with return code 572
[task 2020-02-27T23:49:43.620Z] 23:49:43 INFO - PROCESS LEAKS None
[task 2020-02-27T23:49:43.620Z] 23:49:43 INFO - PROCESS LEAKS None
[task 2020-02-27T23:49:43.621Z] 23:49:43 INFO - Closing logging queue
[task 2020-02-27T23:49:43.621Z] 23:49:43 INFO - queue closed
[task 2020-02-27T23:49:43.640Z] 23:49:43 INFO - Setting up ssl
[task 2020-02-27T23:49:44.007Z] 23:49:44 INFO - certutil |
[task 2020-02-27T23:49:44.383Z] 23:49:44 INFO - certutil |
[task 2020-02-27T23:49:44.801Z] 23:49:44 INFO - certutil |
[task 2020-02-27T23:49:44.801Z] 23:49:44 INFO - Certificate Nickname Trust Attributes
[task 2020-02-27T23:49:44.801Z] 23:49:44 INFO - SSL,S/MIME,JAR/XPI
[task 2020-02-27T23:49:44.801Z] 23:49:44 INFO -
[task 2020-02-27T23:49:44.801Z] 23:49:44 INFO - web-platform-tests CT,,
[task 2020-02-27T23:49:44.801Z] 23:49:44 INFO -
[task 2020-02-27T23:49:45.097Z] 23:49:45 INFO - Application command: Z:\task_1582843161\build\application\firefox\firefox.exe -marionette about:blank --wait-for-browser -profile c:\users\task_1582843161\appdata\local\temp\tmpvqnuls.mozrunner

Geoff do you have any suggestions here?

Although this bug has been around for a while, there was a large increase in failure frequency around Feb 25. I note especially:

https://treeherder.mozilla.org/#/jobs?repo=mozilla-central&searchStr=windows%2Cccov%2Cweb-platform&tochange=7f41334e10443f4f1c7426e86fb0cb7adfdf4d62&fromchange=7d59549f2fda3aed3927ab49b940d9024e161798

Pointing to
https://hg.mozilla.org/mozilla-central/pushloghtml?changeset=f3da8ae9d1a3e74cd273746da51a035ddc572bee

There's a lot in there.

Bug 1617886 jumps out at me as a possibility - could someone try backing that out on try to see if it helps?

Try push with Bug 1617886 backed out https://treeherder.mozilla.org/#/jobs?repo=try&group_state=expanded&revision=1af211b9c19e0362c31f0e8fd82ca86af2e5e1d6.
Will update with the results.
LE: try is green. OK to go ahead with the backout?

Geoff, any thoughts about what the next action should be here? Thank you.

Let's check with jgraham before taking any action.

James can you take a look?
Please also take into consideration https://bugzilla.mozilla.org/show_bug.cgi?id=1618238#c3

So we can back that out if we need to, but it's a pretty big performance win, so it seems pretty unfortunate. I have a patch to increase the timeout for opening the window; dunno if that's going to help but we could try it first.

We'll wait for your patch. Thanks.

James did you patch land? is there an ETA if it hasn't?

Oh right. So I realised there's a problem with the patch in that it bumps against the overall timeout for running a test. I'll look at this some more in the next day or so.

thank you.

Hi James, are there any updates here?

There are 28 total failures in the last 7 days on windows10-64-ccov opt platform.

Recent failure log: https://treeherder.mozilla.org/logviewer.html#/jobs?job_id=295243199&repo=mozilla-central&lineNumber=2501

There are 33 total failures in the last 7 days on windows10-64-ccov opt platform.

James, are you still working on this?

James, we've seen a spike of these failures lately on windows10-64-ccov, they look to be permafailing:
https://treeherder.mozilla.org/#/jobs?repo=mozilla-central&group_state=expanded&searchStr=windows%2C10%2Cx64%2Cccov%2Copt%2Cweb%2Cplatform%2Ctests%2Ctest-windows10-64-ccov%2Fopt-web-platform-tests-e10s&tochange=da2b1829e1fd5bb09b405214cfb8d80bd911f111&fromchange=6663d3dc883b6ad0d0dfa9346f9ceabf2b2c7967&selectedJob=297136293

Could they be caused by Bug 1626089 as well?

Looked over the last 20 logs and the tests failure are as follows:

• offscreen-canvas/drawing-images-to-the-canvas/2d.drawImage.zerocanvas.worker.html

• offscreen-canvas/path-objects/2d.path.rect.selfintersect.worker.html

• offscreen-canvas/compositing/2d.composite.solid.destination-in.html

• offscreen-canvas/compositing/2d.composite.solid.destination-out.html

• offscreen-canvas/pixel-manipulation/2d.imageData.put.path.html

• offscreen-canvas/pixel-manipulation/2d.imageData.put.null.worker.html

• css/css-grid/alignment/grid-self-alignment-stretch-009.html

• css/css-grid/alignment/grid-self-alignment-stretch-002.html

• css/css-grid/alignment/grid-self-alignment-stretch-003.html

• css/css-grid/alignment/grid-self-alignment-stretch-001.html

• css/css-grid/alignment/grid-self-alignment-stretch-008.html

• html/webappapis/dynamic-markup-insertion/opening-the-input-stream/url.window.html

• html/webappapis/dynamic-markup-insertion/opening-the-input-stream/url-fragment.window.html

• xhr/xmlhttprequest-timeout-aborted.html?aborted immediately after send()

• xhr/xmlhttprequest-sync-not-hang-scriptloader.html

• css/cssom/at-namespace.html

• css/cssom/CSSStyleSheet.html

• 2dcontext/fill-and-stroke-styles/2d.pattern.repeat.unrecognised.html

• html/semantics/embedded-content/media-elements/track/track-element/track-webvtt-valign.html

James can you take a look? Or can you assign someone to work on this?

Over the last 7 days there are 119 failures on this bug. These happen on android-em-7-0-x86_64, linux1804-64-ccov, windows10-64-ccov
Here is the most recent failure log: https://treeherder.mozilla.org/logviewer.html#/jobs?job_id=298888612&repo=mozilla-central&lineNumber=5546

In the last 7 days there have been 85 occurrences on windows10-64-ccov opt.

Recent failure: https://treeherder.mozilla.org/logviewer.html#/jobs?job_id=300444504&repo=mozilla-central&lineNumber=3126

James are you working on this?

A wpt2 job on windows 10 ccov is permafailing with this issue since the wptsync from May 2nd:
https://treeherder.mozilla.org/#/jobs?repo=mozilla-central&searchStr=windows%2C10%2Cx64%2Cccov%2Copt%2Cweb%2Cplatform%2Ctests%2C%28backlog%29%2Ctest-windows10-64-ccov%2Fopt-web-platform-tests-backlog-e10s&fromchange=dc66e0f1f868138c27f6efe470e8af53261c9ad5&tochange=5daf558349272b05cee2c9097a9499ff4d7363e6&selectedTaskRun=fvOr8ydMQ3-fL0DP7d1GTg-0

James, could you please take a look?

James can you assign someone to work on this?

We had 53 occurrences in the past week all on windows10-64-ccov opt.
Recent failure: https://treeherder.mozilla.org/logviewer.html#/jobs?job_id=303444106&repo=mozilla-central&lineNumber=4048

[task 2020-05-23T00:49:37.788Z] 00:49:37 INFO - TEST-START | /dom/ranges/Range-mutations-insertBefore.html
[task 2020-05-23T00:49:37.798Z] 00:49:37 INFO - Closing window 70
[task 2020-05-23T00:49:37.857Z] 00:49:37 INFO - PID 2800 | ###!!! [Parent][RunMessage] Error: Channel closing: too late to send/recv, messages will be lost
[task 2020-05-23T00:49:58.036Z] 00:49:58 WARNING - Traceback (most recent call last):
[task 2020-05-23T00:49:58.036Z] 00:49:58 WARNING - File "Z:\task_1590191754\build\tests\web-platform\tests\tools\wptrunner\wptrunner\executors\executormarionette.py", line 642, in run_func
[task 2020-05-23T00:49:58.036Z] 00:49:58 WARNING - self.result = True, self.func(self.protocol, self.url, self.timeout)
[task 2020-05-23T00:49:58.036Z] 00:49:58 WARNING - File "Z:\task_1590191754\build\tests\web-platform\tests\tools\wptrunner\wptrunner\executors\executormarionette.py", line 747, in do_testharness
[task 2020-05-23T00:49:58.036Z] 00:49:58 WARNING - timeout=10self.timeout_multiplier)
[task 2020-05-23T00:49:58.036Z] 00:49:58 WARNING - File "Z:\task_1590191754\build\tests\web-platform\tests\tools\wptrunner\wptrunner\executors\executormarionette.py", line 234, in get_test_window
[task 2020-05-23T00:49:58.036Z] 00:49:58 WARNING - raise Exception("unable to find test window")
[task 2020-05-23T00:49:58.036Z] 00:49:58 WARNING - Exception: unable to find test window
[task 2020-05-23T00:49:58.036Z] 00:49:58 WARNING -
[task 2020-05-23T00:49:58.037Z] 00:49:58 INFO - TEST-UNEXPECTED-ERROR | /dom/ranges/Range-mutations-insertBefore.html | unable to find test window
[task 2020-05-23T00:49:58.037Z] 00:49:58 INFO - Traceback (most recent call last):
[task 2020-05-23T00:49:58.037Z] 00:49:58 INFO - File "Z:\task_1590191754\build\tests\web-platform\tests\tools\wptrunner\wptrunner\executors\executormarionette.py", line 642, in run_func
[task 2020-05-23T00:49:58.037Z] 00:49:58 INFO - self.result = True, self.func(self.protocol, self.url, self.timeout)
[task 2020-05-23T00:49:58.037Z] 00:49:58 INFO - File "Z:\task_1590191754\build\tests\web-platform\tests\tools\wptrunner\wptrunner\executors\executormarionette.py", line 747, in do_testharness
[task 2020-05-23T00:49:58.037Z] 00:49:58 INFO - timeout=10self.timeout_multiplier)
[task 2020-05-23T00:49:58.037Z] 00:49:58 INFO - File "Z:\task_1590191754\build\tests\web-platform\tests\tools\wptrunner\wptrunner\executors\executormarionette.py", line 234, in get_test_window
[task 2020-05-23T00:49:58.037Z] 00:49:58 INFO - raise Exception("unable to find test window")
[task 2020-05-23T00:49:58.037Z] 00:49:58 INFO - Exception: unable to find test window
[task 2020-05-23T00:49:58.037Z] 00:49:58 INFO - TEST-INFO took 20242ms
[task 2020-05-23T00:49:58.056Z] 00:49:58 INFO - PID 2800 | 1590194998048 Marionette INFO Stopped listening on port 53019
[task 2020-05-23T00:49:58.197Z] 00:49:58 INFO - PID 2800 | ###!!! [Parent][RunMessage] Error: Channel closing: too late to send/recv, messages will be lost
[task 2020-05-23T00:50:08.076Z] 00:50:08 INFO - PID 2800 | WARNING: At least one completion condition is taking too long to complete. Conditions: [{"name":"SessionStore: flushing all windows","state":{"total":1,"current":0},"filename":"resource:///modules/sessionstore/SessionStore.jsm","lineNumber":2205,"stack":["resource:///modules/sessionstore/SessionStore.jsm:ssi_onQuitApplicationGranted:2205","resource:///modules/sessionstore/SessionStore.jsm:ssi_observe:915","chrome://marionette/content/driver.js:GeckoDriver.prototype.quit:3514","chrome://marionette/content/server.js:despatch:305","chrome://marionette/content/server.js:execute:275","chrome://marionette/content/server.js:onPacket/<:248","chrome://marionette/content/server.js:onPacket:249","chrome://marionette/content/transport.js:_onJSONObjectReady/<:501"]}] Barrier: quit-application-granted
[task 2020-05-23T00:50:09.030Z] 00:50:09 INFO - Browser exited with return code 572
[task 2020-05-23T00:50:09.031Z] 00:50:09 INFO - PROCESS LEAKS None

There are 48 total failures in the last 7 days: https://treeherder.mozilla.org/intermittent-failures.html#/bugdetails?startday=2020-05-24&endday=2020-05-31&tree=trunk&bug=1522333

Recent failure log: https://treeherder.mozilla.org/logviewer.html#/jobs?job_id=304399186&repo=mozilla-central&lineNumber=3410