STR: 1) Go to http://www.jw.org/fr/la-bible-et-vous/familles/enfants/deviens-l-ami-de-jehovah/videos/ 2) Click on the 1st video called "Pour les parents" and wait for its start. NB: with FF26 there is a loading error, only audio is present, video is missing, but it doesn't impact the STR. 3) Close the video overlay (with the button "Fermer" on the top right) 4) Click on the 2nd video called "Obéis à tes parents" and wait for its start. 5) Close tge video overlay? Result: crash CR: https://crash-stats.mozilla.com/report/index/e506e2eb-fbec-469d-8904-554492140107 Frame Module Signature Source 0 xul.dll mozilla::layers::ImageContainer::CreateImage(mozilla::ImageFormat const *,unsigned int) gfx/layers/ImageContainer.cpp 1 xul.dll mozilla::D3D9DXVA2Manager::CopyToImage(IMFSample *,nsIntRect const &,mozilla::layers::ImageContainer *,mozilla::layers::Image * *) content/media/wmf/DXVA2Manager.cpp 2 xul.dll mozilla::WMFReader::CreateD3DVideoFrame(IMFSample *,__int64,__int64,__int64,mozilla::VideoData * *) content/media/wmf/WMFReader.cpp 3 xul.dll mozilla::WMFReader::DecodeVideoFrame(bool &,__int64) content/media/wmf/WMFReader.cpp 4 xul.dll mozilla::MediaDecoderReader::DecodeToFirstVideoData() content/media/MediaDecoderReader.cpp 5 xul.dll mozilla::MediaDecoderReader::FindStartTime(__int64 &) content/media/MediaDecoderReader.cpp 6 xul.dll mozilla::MediaDecoderStateMachine::FindStartTime() content/media/MediaDecoderStateMachine.cpp 7 xul.dll mozilla::MediaDecoderStateMachine::DecodeMetadata() content/media/MediaDecoderStateMachine.cpp 8 xul.dll mozilla::MediaDecoderStateMachine::DecodeThreadRun() content/media/MediaDecoderStateMachine.cpp 9 xul.dll nsRunnableMethodImpl<tag_nsresult ( nsIScriptElement::*)(void),void,1>::Run() obj-firefox/dist/include/nsThreadUtils.h 10 xul.dll nsThread::ProcessNextEvent(bool,bool *) xpcom/threads/nsThread.cpp 11 xul.dll NS_ProcessNextEvent(nsIThread *,bool) xpcom/glue/nsThreadUtils.cpp 12 xul.dll mozilla::ipc::MessagePumpForNonMainThreads::Run(base::MessagePump::Delegate *) ipc/glue/MessagePump.cpp 13 xul.dll MessageLoop::RunHandler() ipc/chromium/src/base/message_loop.cc 14 xul.dll MessageLoop::Run() ipc/chromium/src/base/message_loop.cc 15 xul.dll nsThread::ThreadFunc(void *) xpcom/threads/nsThread.cpp 16 nss3.dll _PR_NativeRunThread nsprpub/pr/src/threads/combined/pruthr.c 17 nss3.dll pr_root nsprpub/pr/src/md/windows/w95thred.c 18 msvcr100.dll _callthreadstartex f:\dd\vctools\crt_bld\self_x86\crt\src\threadex.c 19 msvcr100.dll _threadstartex f:\dd\vctools\crt_bld\self_x86\crt\src\threadex.c 20 kernel32.dll BaseThreadInitThunk 21 ntdll.dll __RtlUserThreadStart 22 ntdll.dll _RtlUserThreadStart

Sorry, step 5) is "Close the video overlay" of course. ;)

looks like Bug 945645

Probably, yes.

Fixed by bug 945645.