STR: 1. Using a debug Firefox build, open Gmail. 2. Click the "Compose" button. 3. *Quickly* click the draft email's "Discard draft" trash can button. 4. Quit Firefox. RESULT: ###!!! ABORT: not on worker thread!: 'mWorkerLoopID == MessageLoop::current()->id()', file ../../dist/include/mozilla/ipc/MessageChannel.h, line 401 This assertion failure is 100% reproducible if you do not wait too long between clicking the "Compose" and "Discard draft" buttons. It looks similar to Firefox OS bug 1028645 and bug 1117402. [Child 31394] ###!!! ABORT: not on worker thread!: 'mWorkerLoopID == MessageLoop::current()->id()', file ../../dist/include/mozilla/ipc/MessageChannel.h, line 401 #01: mozilla::ipc::MessageChannel::Send(IPC::Message*)[/Users/chris/Code/mozilla/inbound/objdir-osx/dist/NightlyDebug.app/Contents/MacOS/XUL +0x46618b] #02: mozilla::layers::PTextureChild::SendRemoveTexture()[/Users/chris/Code/mozilla/inbound/objdir-osx/dist/NightlyDebug.app/Contents/MacOS/XUL +0x7935cf] #03: mozilla::layers::TextureClient::ForceRemove()[/Users/chris/Code/mozilla/inbound/objdir-osx/dist/NightlyDebug.app/Contents/MacOS/XUL +0xbc5409] #04: mozilla::layers::ShadowLayerForwarder::RemoveTexture(mozilla::layers::TextureClient*)[/Users/chris/Code/mozilla/inbound/objdir-osx/dist/NightlyDebug.app/Contents/MacOS/XUL +0xc0dca7] #05: mozilla::layers::TextureClient::Finalize()[/Users/chris/Code/mozilla/inbound/objdir-osx/dist/NightlyDebug.app/Contents/MacOS/XUL +0xbc567b] #06: mozilla::AtomicRefCountedWithFinalize<mozilla::layers::TextureClient>::Release()[/Users/chris/Code/mozilla/inbound/objdir-osx/dist/NightlyDebug.app/Contents/MacOS/XUL +0xb594a1] #07: PL_DHashTableFinish(PLDHashTable*)[/Users/chris/Code/mozilla/inbound/objdir-osx/dist/NightlyDebug.app/Contents/MacOS/XUL +0xfd201] #08: mozilla::layers::CairoImage::~CairoImage()[/Users/chris/Code/mozilla/inbound/objdir-osx/dist/NightlyDebug.app/Contents/MacOS/XUL +0xb58c6e] #09: mozilla::layers::CairoImage::~CairoImage()[/Users/chris/Code/mozilla/inbound/objdir-osx/dist/NightlyDebug.app/Contents/MacOS/XUL +0xb58d1e] #10: mozilla::layers::Image::Release()[/Users/chris/Code/mozilla/inbound/objdir-osx/dist/NightlyDebug.app/Contents/MacOS/XUL +0x95cee0] #11: mozilla::layers::ImageContainer::~ImageContainer()[/Users/chris/Code/mozilla/inbound/objdir-osx/dist/NightlyDebug.app/Contents/MacOS/XUL +0xb57c72] #12: mozilla::layers::ImageContainer::Release()[/Users/chris/Code/mozilla/inbound/objdir-osx/dist/NightlyDebug.app/Contents/MacOS/XUL +0x96be0f] #13: mozilla::image::RasterImage::~RasterImage()[/Users/chris/Code/mozilla/inbound/objdir-osx/dist/NightlyDebug.app/Contents/MacOS/XUL +0xca41ec] #14: mozilla::image::RasterImage::~RasterImage()[/Users/chris/Code/mozilla/inbound/objdir-osx/dist/NightlyDebug.app/Contents/MacOS/XUL +0xca435e] #15: mozilla::image::RasterImage::Release()[/Users/chris/Code/mozilla/inbound/objdir-osx/dist/NightlyDebug.app/Contents/MacOS/XUL +0xca3b41] #16: imgRequest::~imgRequest()[/Users/chris/Code/mozilla/inbound/objdir-osx/dist/NightlyDebug.app/Contents/MacOS/XUL +0xcbe141] #17: imgRequest::~imgRequest()[/Users/chris/Code/mozilla/inbound/objdir-osx/dist/NightlyDebug.app/Contents/MacOS/XUL +0xcbe22e] #18: imgRequest::Release()[/Users/chris/Code/mozilla/inbound/objdir-osx/dist/NightlyDebug.app/Contents/MacOS/XUL +0xcbd91e] #19: imgCacheEntry::Release()[/Users/chris/Code/mozilla/inbound/objdir-osx/dist/NightlyDebug.app/Contents/MacOS/XUL +0xcba235] #20: nsTArray_Impl<nsRefPtr<imgCacheEntry>, nsTArrayInfallibleAllocator>::RemoveElementsAt(unsigned long, unsigned long)[/Users/chris/Code/mozilla/inbound/objdir-osx/dist/NightlyDebug.app/Contents/MacOS/XUL +0xcbcf5d] #21: imgLoader::EvictEntries(nsRefPtrHashtable<nsCStringHashKey, imgCacheEntry>&)[/Users/chris/Code/mozilla/inbound/objdir-osx/dist/NightlyDebug.app/Contents/MacOS/XUL +0xcb1dec] #22: imgLoader::~imgLoader()[/Users/chris/Code/mozilla/inbound/objdir-osx/dist/NightlyDebug.app/Contents/MacOS/XUL +0xcb0d88] #23: imgLoader::~imgLoader()[/Users/chris/Code/mozilla/inbound/objdir-osx/dist/NightlyDebug.app/Contents/MacOS/XUL +0xcb104e] #24: imgLoader::Release()[/Users/chris/Code/mozilla/inbound/objdir-osx/dist/NightlyDebug.app/Contents/MacOS/XUL +0xcb06f5] #25: imgLoader::Shutdown()[/Users/chris/Code/mozilla/inbound/objdir-osx/dist/NightlyDebug.app/Contents/MacOS/XUL +0xcb1ca5] #26: mozilla::image::ShutdownModule()[/Users/chris/Code/mozilla/inbound/objdir-osx/dist/NightlyDebug.app/Contents/MacOS/XUL +0xcfca25] #27: LayoutModuleDtor()[/Users/chris/Code/mozilla/inbound/objdir-osx/dist/NightlyDebug.app/Contents/MacOS/XUL +0x28764a1] #28: nsTArray_Impl<nsAutoPtr<nsComponentManagerImpl::KnownModule>, nsTArrayInfallibleAllocator>::RemoveElementsAt(unsigned long, unsigned long)[/Users/chris/Code/mozilla/inbound/objdir-osx/dist/NightlyDebug.app/Contents/MacOS/XUL +0xc025c] #29: nsComponentManagerImpl::Shutdown()[/Users/chris/Code/mozilla/inbound/objdir-osx/dist/NightlyDebug.app/Contents/MacOS/XUL +0xbbb72] #30: mozilla::ShutdownXPCOM(nsIServiceManager*)[/Users/chris/Code/mozilla/inbound/objdir-osx/dist/NightlyDebug.app/Contents/MacOS/XUL +0x104a93] #31: XRE_TermEmbedding[/Users/chris/Code/mozilla/inbound/objdir-osx/dist/NightlyDebug.app/Contents/MacOS/XUL +0x2cf4f71] #32: mozilla::ipc::ScopedXREEmbed::Stop()[/Users/chris/Code/mozilla/inbound/objdir-osx/dist/NightlyDebug.app/Contents/MacOS/XUL +0x46ebb3] #33: XRE_InitChildProcess[/Users/chris/Code/mozilla/inbound/objdir-osx/dist/NightlyDebug.app/Contents/MacOS/XUL +0x2cf5804] #34: content_process_main(int, char**)[/Users/chris/Code/mozilla/inbound/objdir-osx/dist/NightlyDebug.app/Contents/MacOS/plugin-container.app/Contents/MacOS/plugin-container +0x1b72]