09:24:58 INFO - 1700 INFO TEST-START | editor/libeditor/tests/test_bug1140105.html 09:24:58 INFO - MEMORY STAT vsize after test: 1020710912 09:24:58 INFO - MEMORY STAT vsizeMaxContiguous after test: 8072559689728 09:24:58 INFO - MEMORY STAT residentFast after test: 377741312 09:24:58 INFO - MEMORY STAT heapAllocated after test: 116987200 09:24:58 INFO - 1701 INFO TEST-OK | editor/libeditor/tests/test_bug1140105.html | took 57ms 09:24:58 INFO - 1702 INFO TEST-START | editor/libeditor/tests/test_bug1154791.html 09:24:58 INFO - 1703 INFO must wait for load 09:24:58 INFO - 1704 INFO TEST-UNEXPECTED-FAIL | editor/libeditor/tests/test_bug1154791.html | We should have two misspelled words - got 0, expected 2 09:24:58 INFO - 1705 INFO TEST-UNEXPECTED-FAIL | editor/libeditor/tests/test_bug1154791.html | uncaught exception - IndexSizeError: Index or size is negative or greater than the allowed amount at chrome://mochitests/content/chrome/editor/libeditor/tests/test_bug1154791.html:41 09:24:58 INFO - JavaScript error: chrome://mochitests/content/chrome/editor/libeditor/tests/test_bug1154791.html, line 41: IndexSizeError: Index or size is negative or greater than the allowed amount 09:24:58 INFO - MEMORY STAT vsize after test: 1020907520 09:24:58 INFO - MEMORY STAT vsizeMaxContiguous after test: 8072559689728 09:24:58 INFO - MEMORY STAT residentFast after test: 380116992 09:24:58 INFO - MEMORY STAT heapAllocated after test: 119045992 09:24:58 INFO - 1706 INFO TEST-OK | editor/libeditor/tests/test_bug1154791.html | took 73ms

Do you have more detail? When did this start failing? On which platform? Is it really intermittent or always?

Expand comment 1 for more information. (In reply to Treeherder Robot from comment #1) > log: > https://treeherder.mozilla.org/logviewer.html#?repo=mozilla- > inbound&job_id=9332099 > repository: mozilla-inbound > start_time: 2015-04-27T09:16:04 > who: rvandermeulen[at]mozilla[dot]com > machine: t-w864-ix-137 > buildname: Windows 8 64-bit mozilla-inbound opt test mochitest-other > revision: 46baca316516 And it's intermittent (just filed on the first instance of it). You'll see more Treeherder Robot comments in this bug when it's hit in the future.

I think we may need to yield to the event loop before reading the spelling suggestions. I'm pushing a patch to do that, let's see if this fails again after that.