as seen on try server: https://treeherder.mozilla.org/#/jobs?repo=try&revision=72b7fdf2885a&filter-searchStr=mochitest-5%20win%20debug 02:21:28 INFO - TEST-INFO | leakcheck | default process: leak threshold set at 0 bytes 02:21:28 INFO - TEST-INFO | leakcheck | plugin process: leak threshold set at 0 bytes 02:21:28 INFO - TEST-INFO | leakcheck | tab process: leak threshold set at 25000 bytes 02:21:28 INFO - TEST-INFO | leakcheck | geckomediaplugin process: leak threshold set at 20000 bytes 02:21:28 INFO - == BloatView: ALL (cumulative) LEAK AND BLOAT STATISTICS, default process 3876 02:21:28 INFO - |<----------------Class--------------->|<-----Bytes------>|<----Objects---->| 02:21:28 INFO - | | Per-Inst Leaked| Total Rem| 02:21:28 INFO - 0 |TOTAL | 20 1512|101456900 12| 02:21:28 INFO - 226 |EventTokenBucket | 232 464| 2 2| 02:21:28 INFO - 380 |Mutex | 32 64| 10935 2| 02:21:28 INFO - 489 |ReentrantMonitor | 40 80| 6526 2| 02:21:28 INFO - 874 |nsDeque | 96 96| 28502 1| 02:21:28 INFO - 1218 |nsSocketTransportService | 272 272| 1 1| 02:21:28 INFO - 1275 |nsTArray_base | 8 8|28390753 1| 02:21:28 INFO - 1285 |nsThread | 240 240| 58 1| 02:21:28 INFO - 1290 |nsTimerImpl | 144 288| 17763 2| 02:21:28 INFO - nsTraceRefcnt::DumpStatistics: 1399 entries 02:21:28 INFO - TEST-INFO | leakcheck | default process: leaked 2 EventTokenBucket (464 bytes) 02:21:28 INFO - TEST-INFO | leakcheck | default process: leaked 2 Mutex (64 bytes) 02:21:28 INFO - TEST-INFO | leakcheck | default process: leaked 2 ReentrantMonitor (80 bytes) 02:21:28 INFO - TEST-INFO | leakcheck | default process: leaked 1 nsDeque (96 bytes) 02:21:28 INFO - TEST-INFO | leakcheck | default process: leaked 1 nsSocketTransportService (272 bytes) 02:21:28 INFO - TEST-INFO | leakcheck | default process: leaked 1 nsTArray_base (8 bytes) 02:21:28 INFO - TEST-INFO | leakcheck | default process: leaked 1 nsThread (240 bytes) 02:21:28 INFO - TEST-INFO | leakcheck | default process: leaked 2 nsTimerImpl (288 bytes) 02:21:28 WARNING - TEST-UNEXPECTED-FAIL | leakcheck | default process: 1512 bytes leaked (EventTokenBucket, Mutex, ReentrantMonitor, nsDeque, nsSocketTransportService, ...) I need to bisect this down a bit to try and find the root cause.

narrowed it down to: [test_viewport_units.html] [test_visited_image_loading.html] [test_visited_image_loading_empty.html] [test_visited_lying.html] [test_visited_pref.html] [test_visited_reftests.html] [test_bug525952.html] waiting on try results, this should be known later today of the root cause.

and the winner is.... test_visited_reftests.html (https://dxr.mozilla.org/mozilla-central/source/layout/style/test/test_visited_reftests.html) I am glad that this is a single file, now to figure out. :dbaron, I see that you have edited this file a lot in the history of it. Can you look at this or help me find someone to look at it?

oh, this is 2 months outdated- we might go ahead and disable this test until there is more time to look into it.

This is all green : https://treeherder.mozilla.org/#/jobs?repo=try&revision=0c1a6d3354bf&filter-searchStr=windows%20m%285%29

closing as worksforme then, thanks for double checking here.