It's similar to bug 767343. It first appeared in 16.0a1/20120620. Signature mozalloc_abort(char const* const) | NS_DebugBreak_P | nsACString_internal::MutatePrep(unsigned int, char**, unsigned int*) More Reports Search UUID 2563075a-b445-49df-ae32-59fd72120722 Date Processed 2012-07-22 19:38:26 Uptime 373 Last Crash 7.1 minutes before submission Install Age 2.9 hours since version was first installed. Install Time 2012-07-22 16:40:59 Product Firefox Version 17.0a1 Build ID 20120722030555 Release Channel nightly OS Windows NT OS Version 6.1.7601 Service Pack 1 Build Architecture x86 Build Architecture Info GenuineIntel family 6 model 15 stepping 6 Crash Reason EXCEPTION_BREAKPOINT Crash Address 0x72381999 App Notes AdapterVendorID: 0x1002, AdapterDeviceID: 0x71c5, AdapterSubsysID: 00681854, AdapterDriverVersion: 8.561.0.0 DWrite? DWrite+ D3D10 Layers? D3D10 Layers- D3D9 Layers? D3D9 Layers- xpcom_runtime_abort(###!!! ABORT: OOM: file e:\builds\moz2_slave\m-cen-w32-ntly\build\xpcom\string\src\nsTSubstring.cpp, line 533) EMCheckCompatibility False Adapter Vendor ID 0x1002 Adapter Device ID 0x71c5 Total Virtual Memory 2147352576 Available Virtual Memory 349659136 System Memory Use Percentage 87 Available Page File 2240040960 Available Physical Memory 341073920 Frame Module Signature Source 0 mozalloc.dll mozalloc_abort memory/mozalloc/mozalloc_abort.cpp:23 1 xul.dll NS_DebugBreak_P xpcom/base/nsDebugImpl.cpp:410 2 xul.dll nsACString_internal::MutatePrep xpcom/string/src/nsTSubstring.cpp:130 3 xul.dll nsScriptableInputStream::ReadBytes xpcom/io/nsScriptableInputStream.cpp:66 4 xul.dll XPCWrappedNative::CallMethod js/xpconnect/src/XPCWrappedNative.cpp:2382 5 xul.dll XPC_WN_CallMethod js/xpconnect/src/XPCWrappedNativeJSOps.cpp:1474 6 mozjs.dll js::InvokeKernel js/src/jsinterp.cpp:345 7 mozjs.dll js::Interpret js/src/jsinterp.cpp:2426 8 mozjs.dll js::InvokeKernel js/src/jsinterp.cpp:356 9 mozjs.dll js::Invoke js/src/jsinterp.cpp:388 10 mozjs.dll js::CrossCompartmentWrapper::call js/src/jswrapper.cpp:708 11 mozjs.dll proxy_Call js/src/jsproxy.cpp:1682 ... More reports at: https://crash-stats.mozilla.com/report/list?signature=mozalloc_abort%28char+const*+const%29+|+NS_DebugBreak_P+|+nsACString_internal%3A%3AMutatePrep%28unsigned+int%2C+char**%2C+unsigned+int*%29

it has something to do with cache. removing files in cache directory resolved problem with similar sympthoms for me

Closing because no crash reported since 12 weeks.

Closing because no crash reported since 12 weeks.