Seen while reviewing the Explosive Report for 8 - https://crash-analysis.mozilla.com/rkaiser/2011-12-01/2011-12-01.firefox.8.explosiveness.html. https://crash-stats.mozilla.com/report/list?signature=mozalloc_abort%28char%20const*%20const%29%20|%20NS_DebugBreak_P%20|%20mozilla::layers::ReadbackManagerD3D10::~ReadbackManagerD3D10%28%29. Happens on versions up to trunk. One comment mentions beta nvidia driver 290.36. https://crash-stats.mozilla.com/report/index/3e9a146e-066e-4131-a6e3-395d72111130 Frame Module Signature [Expand] Source 0 mozalloc.dll mozalloc_abort memory/mozalloc/mozalloc_abort.cpp:77 1 xul.dll NS_DebugBreak_P xpcom/base/nsDebugImpl.cpp:345 2 xul.dll mozilla::layers::ReadbackManagerD3D10::~ReadbackManagerD3D10 gfx/layers/d3d10/ReadbackManagerD3D10.cpp:160 3 xul.dll mozilla::layers::ReadbackManagerD3D10::`scalar deleting destructor' 4 xul.dll mozilla::layers::ReadbackManagerD3D10::Release gfx/layers/d3d10/ReadbackManagerD3D10.cpp:213 5 xul.dll nsRefPtr<nsBarProp>::assign_with_AddRef 6 xul.dll mozilla::layers::LayerManagerD3D10::`vector deleting destructor' 7 xul.dll mozilla::layers::LayerManager::Release 8 xul.dll nsXULWindow::Destroy xpfe/appshell/src/nsXULWindow.cpp:556 9 xul.dll nsWebShellWindow::Destroy xpfe/appshell/src/nsWebShellWindow.cpp:784 10 xul.dll nsWebShellWindow::HandleEvent 11 xul.dll nsWindow::DispatchEvent widget/src/windows/nsWindow.cpp:3598 12 xul.dll nsWindow::DispatchWindowEvent widget/src/windows/nsWindow.cpp:3636 13 xul.dll nsWindow::DispatchStandardEvent widget/src/windows/nsWindow.cpp:3629 14 xul.dll nsWindow::ProcessMessage 15 xul.dll nsWindow::WindowProcInternal widget/src/windows/nsWindow.cpp:4469 16 xul.dll CallWindowProcCrashProtected xpcom/base/nsCrashOnException.cpp:65 17 xul.dll nsWindow::WindowProc widget/src/windows/nsWindow.cpp:4411 18 user32.dll InternalCallWinProc 19 user32.dll UserCallWinProcCheckWow 20 user32.dll DispatchClientMessage 21 user32.dll __fnDWORD 22 ntdll.dll KiUserCallbackDispatcher 23 ntdll.dll KiUserApcDispatcher 24 user32.dll RealDefWindowProcW 25 uxtheme.dll DoMsgDefault 26 uxtheme.dll OnDwpSysCommand 27 uxtheme.dll _ThemeDefWindowProc 28 uxtheme.dll ThemeDefWindowProcW 29 user32.dll GetRealWindowOwner 30 user32.dll InternalCallWinProc 31 user32.dll UserCallWinProcCheckWow 32 user32.dll CallWindowProcAorW 33 user32.dll CallWindowProcW 34 xul.dll nsWindow::WindowProcInternal widget/src/windows/nsWindow.cpp:4474 35 xul.dll CallWindowProcCrashProtected xpcom/base/nsCrashOnException.cpp:65 36 xul.dll nsWindow::WindowProc widget/src/windows/nsWindow.cpp:4411 37 user32.dll InternalCallWinProc 38 user32.dll GetRealWindowOwner 39 user32.dll DispatchMessageWorker 40 user32.dll DispatchMessageW 41 xul.dll nsAppShell::ProcessNextNativeEvent widget/src/windows/nsAppShell.cpp:344 42 xul.dll nsBaseAppShell::OnProcessNextEvent widget/src/xpwidgets/nsBaseAppShell.cpp:306 43 xul.dll nsThread::ProcessNextEvent xpcom/threads/nsThread.cpp:587 44 nspr4.dll PR_Unlock nsprpub/pr/src/threads/combined/prulock.c:347 45 xul.dll MessageLoop::RunHandler ipc/chromium/src/base/message_loop.cc:201 46 xul.dll _SEH_epilog4 47 xul.dll MessageLoop::Run ipc/chromium/src/base/message_loop.cc:175 48 xul.dll mozilla::css::Loader::CreateSheet layout/style/Loader.cpp:1209 49 xul.dll nsAppShell::Run widget/src/windows/nsAppShell.cpp:258 50 xul.dll nsAppStartup::Run toolkit/components/startup/nsAppStartup.cpp:220 51 xul.dll XRE_main toolkit/xre/nsAppRunner.cpp:3558 52 firefox.exe wmain toolkit/xre/nsWindowsWMain.cpp:107 53 firefox.exe firefox.exe@0x4033 54 firefox.exe __tmainCRTStartup crtexe.c:594 55 firefox.exe _SEH_epilog4 56 kernel32.dll BaseThreadInitThunk 57 ntdll.dll __RtlUserThreadStart 58 ntdll.dll LdrpAppendToForwarderList 59 ntdll.dll _RtlUserThreadStart 60 firefox.exe pre_c_init crtexe.c:304 61 firefox.exe pre_c_init crtexe.c:304 62 @0x7ffdefff