While triaging an different assertion from bughunter, I ran into this assertion. 1. Load http://www.minijuegos.com/juego/five-nights-at-freddys-2 2. Wait for the game to load. 3. Shutdown Assertion failure: work_queue_.empty(), at /builds/slave/m-cen-m64-d-000000000000000000/build/src/ipc/chromium/src/base/message_loop.cc:422 I reproduced this on my macbook running OS X 10.9 but not on my local Linux workstation. It has appeared in Bughunter primarily on OS X and Windows though it did appear on one url on Linux but no longer. This assertion was introduced in bug 976363. I manually bisected back most of the year though it is hard to tell when this regressed or if it has always been the case due to other unrelated? crashes.

Note that this is a very common assertion in Bughunter these days with over 1,100 urls reproducing it. However, I can only reproduce on Windows 10. 1. http://www.macworld.co.uk/news/mac/macbook-air-2017-latest-rumours-release-date-uk-price-features-specs-3605337/ 2. wait for page to load, then shutdown browser. 3. Assertion failure: work_queue_.empty(), at c:/builds/moz2_slave/m-cen-w64-d-000000000000000000/build/src/ipc/chromium/src/base/message_loop.cc:410 If you have problems reproducing after the first time, clear you cache and try again. Operating system: Windows NT 10.0.14393 CPU: amd64 family 6 model 45 stepping 2 2 CPUs GPU: UNKNOWN Crash reason: EXCEPTION_BREAKPOINT Crash address: 0x7ffbf9dc26f3 Process uptime: not available Thread 0 (crashed) 0 xul.dll!MessageLoop::DeletePendingTasks() [message_loop.cc:43039280fe46 : 410 + 0x1b] rax = 0x0000000000000000 rdx = 0x000000a1b11ff8d8 rcx = 0x00000000ffffffff rbx = 0x000000000000019a rsi = 0x00000235e7ba4140 rdi = 0x00000235e7ba41c8 rbp = 0x000000a1b11ff930 rsp = 0x000000a1b11ff8c0 r8 = 0x000000a1b11ff8d0 r9 = 0x000000a1b11ff8c8 r10 = 0x0000000000000000 r11 = 0x000000a1b11fae10 r12 = 0x0000000000000001 r13 = 0x00007ffbfe38ead0 r14 = 0xffffffffffffffff r15 = 0x0000000000000000 rip = 0x00007ffbf9dc26f3 Found by: given as instruction pointer in context 1 xul.dll!MessageLoop::~MessageLoop() [message_loop.cc:43039280fe46 : 189 + 0x8] rbx = 0x000000000000019a rbp = 0x000000a1b11ff930 rsp = 0x000000a1b11ff8f0 r12 = 0x0000000000000001 r13 = 0x00007ffbfe38ead0 r14 = 0xffffffffffffffff r15 = 0x0000000000000000 rip = 0x00007ffbf9dbfdfd Found by: call frame info