Filed by: btara [at] mozilla.com
Parsed log: https://treeherder.mozilla.org/logviewer?job_id=330064608&repo=mozilla-central
Full log: https://firefox-ci-tc.services.mozilla.com/api/queue/v1/task/CPk0y4unQOCSbbf3fn66xQ/runs/0/artifacts/public/logs/live_backing.log

[task 2021-02-16T05:04:40.992Z] 05:04:40     INFO - TEST-START | /IndexedDB/structured-clone.any.worker.html?101-last
[task 2021-02-16T05:04:40.993Z] 05:04:40     INFO - Closing window 12884901973
[task 2021-02-16T05:04:44.111Z] 05:04:44     INFO - 
[task 2021-02-16T05:04:44.111Z] 05:04:44     INFO - TEST-PASS | /IndexedDB/structured-clone.any.worker.html?101-last | Array: foo,bar,,,,,,,,,true,false,,,,,,,,,123,456,,,,,,,,, 
[task 2021-02-16T05:04:44.111Z] 05:04:44     INFO - TEST-PASS | /IndexedDB/structured-clone.any.worker.html?101-last | Array: foo,bar 
[task 2021-02-16T05:04:44.111Z] 05:04:44     INFO - TEST-PASS | /IndexedDB/structured-clone.any.worker.html?101-last | Object: [object Object] 
[task 2021-02-16T05:04:44.111Z] 05:04:44     INFO - TEST-PASS | /IndexedDB/structured-clone.any.worker.html?101-last | DOMMatrix: [object DOMMatrix] 
[task 2021-02-16T05:04:44.111Z] 05:04:44     INFO - TEST-PASS | /IndexedDB/structured-clone.any.worker.html?101-last | DOMMatrixReadOnly: [object DOMMatrixReadOnly] 
[task 2021-02-16T05:04:44.112Z] 05:04:44     INFO - TEST-PASS | /IndexedDB/structured-clone.any.worker.html?101-last | DOMPoint: [object DOMPoint] 
[task 2021-02-16T05:04:44.112Z] 05:04:44     INFO - TEST-PASS | /IndexedDB/structured-clone.any.worker.html?101-last | DOMPointReadOnly: [object DOMPointReadOnly] 
[task 2021-02-16T05:04:44.112Z] 05:04:44     INFO - TEST-PASS | /IndexedDB/structured-clone.any.worker.html?101-last | DOMRect: [object DOMRect] 
[task 2021-02-16T05:04:44.112Z] 05:04:44     INFO - TEST-PASS | /IndexedDB/structured-clone.any.worker.html?101-last | DOMRectReadOnly: [object DOMRectReadOnly] 
[task 2021-02-16T05:04:44.112Z] 05:04:44     INFO - TEST-PASS | /IndexedDB/structured-clone.any.worker.html?101-last | ImageData: [object ImageData] 
[task 2021-02-16T05:04:44.113Z] 05:04:44     INFO - TEST-UNEXPECTED-PASS | /IndexedDB/structured-clone.any.worker.html?101-last | Blob: [object Blob] - expected TIMEOUT
[task 2021-02-16T05:04:44.113Z] 05:04:44     INFO - TEST-INFO | expected TIMEOUT
[task 2021-02-16T05:04:44.114Z] 05:04:44     INFO - 
[task 2021-02-16T05:04:44.114Z] 05:04:44     INFO - TEST-UNEXPECTED-PASS | /IndexedDB/structured-clone.any.worker.html?101-last | File: [object File] - expected NOTRUN
[task 2021-02-16T05:04:44.114Z] 05:04:44     INFO - TEST-INFO | expected NOTRUN
[task 2021-02-16T05:04:44.115Z] 05:04:44     INFO - 
[task 2021-02-16T05:04:44.115Z] 05:04:44     INFO - TEST-UNEXPECTED-PASS | /IndexedDB/structured-clone.any.worker.html?101-last | Not serializable: function: function() {} - expected NOTRUN
[task 2021-02-16T05:04:44.115Z] 05:04:44     INFO - TEST-INFO | expected NOTRUN
[task 2021-02-16T05:04:44.117Z] 05:04:44     INFO - 
[task 2021-02-16T05:04:44.117Z] 05:04:44     INFO - TEST-UNEXPECTED-FAIL | /IndexedDB/structured-clone.any.worker.html?101-last | Not serializable: symbol: Symbol(desc) - assert_throws_dom: function "() => store.put(value, 'key')" threw object "TypeError: unsupported type for structured data" that is not a DOMException DataCloneError: property "code" is equal to undefined, expected 25
[task 2021-02-16T05:04:44.117Z] 05:04:44     INFO - cloneFailureTest/<@http://web-platform.test:8000/IndexedDB/structured-clone.any.js:75:22
[task 2021-02-16T05:04:44.117Z] 05:04:44     INFO - TEST-INFO | expected NOTRUN
[task 2021-02-16T05:04:44.118Z] 05:04:44     INFO - 
[task 2021-02-16T05:04:44.118Z] 05:04:44     INFO - TEST-UNEXPECTED-PASS | /IndexedDB/structured-clone.any.worker.html?101-last | Not serializable: DedicatedWorkerGlobalScope: [object DedicatedWorkerGlobalScope] - expected NOTRUN
[task 2021-02-16T05:04:44.118Z] 05:04:44     INFO - TEST-INFO | expected NOTRUN
[task 2021-02-16T05:04:44.119Z] 05:04:44     INFO - 
[task 2021-02-16T05:04:44.119Z] 05:04:44     INFO - TEST-UNEXPECTED-PASS | /IndexedDB/structured-clone.any.worker.html?101-last | Not serializable: Event: [object Event] - expected NOTRUN
[task 2021-02-16T05:04:44.119Z] 05:04:44     INFO - TEST-INFO | expected NOTRUN
[task 2021-02-16T05:04:44.120Z] 05:04:44     INFO - 
[task 2021-02-16T05:04:44.120Z] 05:04:44     INFO - TEST-UNEXPECTED-PASS | /IndexedDB/structured-clone.any.worker.html?101-last | Not serializable: MessageChannel: [object MessageChannel] - expected NOTRUN
[task 2021-02-16T05:04:44.121Z] 05:04:44     INFO - TEST-INFO | expected NOTRUN
[task 2021-02-16T05:04:44.122Z] 05:04:44     INFO - TEST-UNEXPECTED-OK | /IndexedDB/structured-clone.any.worker.html?101-last | expected TIMEOUT
[task 2021-02-16T05:04:44.122Z] 05:04:44     INFO - TEST-INFO expected TIMEOUT | took 3128ms
[task 2021-02-16T05:04:44.124Z] 05:04:44     INFO - PID 3884 | 1613451884121	Marionette	INFO	Stopped listening on port 49913
[task 2021-02-16T05:04:44.462Z] 05:04:44     INFO - Browser exited with return code 0
[task 2021-02-16T05:04:44.462Z] 05:04:44     INFO - PROCESS LEAKS None
[task 2021-02-16T05:04:44.465Z] 05:04:44     INFO - Closing logging queue
[task 2021-02-16T05:04:44.465Z] 05:04:44     INFO - queue closed
[task 2021-02-16T05:04:44.663Z] 05:04:44     INFO - Application command: C:\Users\task_1613442890\build\application\firefox\firefox.exe -marionette about:blank --wait-for-browser -profile C:\Users\task_1613442890\AppData\Local\Temp\tmp8q1k9t83
[task 2021-02-16T05:04:44.666Z] 05:04:44     INFO - PID 9092 | console.warn: SearchSettings: "get: No settings file exists, new profile?" (new Error("", "(unknown module)"))
[task 2021-02-16T05:04:44.667Z] 05:04:44     INFO - PID 9092 | 1613451750564	Marionette	INFO	Listening on port 49914```

https://hg.mozilla.org/mozilla-central/rev/72bc739fca32