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Typing in Korean with spellcheck enabled causes a crash

See original GitHub issue

Describe the bug

Typing in Korean with Spellcheck enabled often crashes Textbox component.

Stack trace:

Index  Function
--------------------------------------------------------------------------------
 1      combase.dll!RoFailFastWithErrorContextInternal2(HRESULT hrError, unsigned long cStowedExceptions, _STOWED_EXCEPTION_INFORMATION_V2 * * aStowedExceptionPointers)
 2      Windows.UI.Xaml.dll!CCoreServices::NWDrawTree(HWWalk * pHWWalk, CWindowRenderTarget * pRenderTarget, VisualTree * pVisualTree, unsigned int forceRedraw, XRECT_WH * prcDirtyRect)
*3      Windows.UI.Xaml.dll!CCoreServices::NWDrawMainTree(CWindowRenderTarget * pIRenderTarget, bool fForceRedraw, XRECT_WH * prcDirtyRect)
 4      Windows.UI.Xaml.dll!CWindowRenderTarget::Draw(CCoreServices * fForceRedraw, unsigned int prcDirtyRect, XRECT_WH *)
 5      Windows.UI.Xaml.dll!CXcpBrowserHost::OnTick()
 6      Windows.UI.Xaml.dll!CXcpDispatcher::Tick()
 7      Windows.UI.Xaml.dll!CXcpDispatcher::OnReentrancyProtectedWindowMessage(HWND__ * msg, unsigned int lParam, unsigned int)
 8      [Inline Frame] Windows.UI.Xaml.dll!CXcpDispatcher::ProcessMessage(HWND__ *)
 9      Windows.UI.Xaml.dll!CXcpDispatcher::WindowProc(HWND__ * hwnd, unsigned int msg, unsigned int wParam, long lParam)
 10     Windows.UI.Xaml.dll!CDeferredInvoke::DispatchQueuedMessage(bool * dispatchedWork, bool * hasMoreWork)
 11     [Inline Frame] Windows.UI.Xaml.dll!CXcpDispatcher::MessageTimerCallback()
 12     Windows.UI.Xaml.dll!CXcpDispatcher::MessageTimerCallbackStatic(void * myUserData)
 13     CoreMessaging.dll!Microsoft__CoreUI__DispatchGroupHandler$CallbackThunk(class System::Delegate *)
 14     CoreMessaging.dll!System::Action::Invoke(void)
 15     CoreMessaging.dll!Microsoft::CoreUI::Dispatch::TimeoutManager::Callback_OnDispatch(void)
 16     CoreMessaging.dll!Microsoft::CoreUI::Dispatch::Dispatcher::DispatchNextItem(void)
 17     CoreMessaging.dll!Microsoft::CoreUI::Dispatch::Dispatcher::Callback_DispatchLoop(struct Microsoft::CoreUI::Dispatch::RunnablePriorityMask)
 18     CoreMessaging.dll!Microsoft::CoreUI::Dispatch::EventLoop::Callback_RunCoreLoop(struct Microsoft::CoreUI::Dispatch::RunMode,bool,bool &)
 19     CoreMessaging.dll!Microsoft::CoreUI::Dispatch::UserAdapterBase::DrainCoreMessagingQueue(struct Microsoft::CoreUI::Dispatch::UserAdapterBase__UserPriority,bool,struct System::IntPtr &)
 20     CoreMessaging.dll!Microsoft::CoreUI::Dispatch::UserAdapter::OnUserDispatch(bool,struct Microsoft::CoreUI::Dispatch::UserAdapterBase__UserPriority,struct System::IntPtr &)
 21     CoreMessaging.dll!Microsoft::CoreUI::Dispatch::UserAdapter::OnUserDispatchRaw(struct System::IntPtr,struct Microsoft::CoreUI::Dispatch::UserAdapterBase__UserPriority,bool,struct System::IntPtr &)
 22     CoreMessaging.dll!Microsoft::CoreUI::Dispatch::UserAdapter_DoWork(struct Microsoft::CoreUI::Dispatch::UserData *,struct Microsoft::CoreUI::Dispatch::UserAdapterBase__UserPriority,bool)
 23     CoreMessaging.dll!Microsoft::CoreUI::Dispatch::UserAdapter_HandleDispatchNotifyMessage(struct HWND__ *,unsigned int,long)
 24     CoreMessaging.dll!Microsoft::CoreUI::Dispatch::UserAdapter_WindowProc(struct HWND__ *,unsigned int,unsigned int,long)
 25     user32.dll!__InternalCallWinProc@20()
 26     user32.dll!UserCallWinProcCheckWow()
 27     user32.dll!DispatchClientMessage()
 28     user32.dll!___fnDWORD@4()
 29     ntdll.dll!_KiUserCallbackDispatcher@12()
 30     user32.dll!PeekMessageW()
 31     combase.dll!CCliModalLoop::MyPeekMessage(tagMSG * pMsg, HWND__ * hwnd, unsigned int min, unsigned int max, unsigned short wFlag)
 32     combase.dll!CCliModalLoop::HandleWakeForMsg()
 33     combase.dll!CCliModalLoop::BlockFn(void * * ahEvent, unsigned long cEvents, unsigned long * lpdwSignaled)
 34     combase.dll!ModalLoop(CSyncClientCall * pClientCall)
 35     combase.dll!ClassicSTAThreadDispatchCrossApartmentCall(tagRPCOLEMESSAGE * pMessage, OXIDEntry * pOXIDEntry, CSyncClientCall * pClientCall)
 36     [Inline Frame] combase.dll!CSyncClientCall::SwitchAptAndDispatchCall(tagRPCOLEMESSAGE * pMessage)
 37     combase.dll!CSyncClientCall::SendReceive2(tagRPCOLEMESSAGE * pMessage, unsigned long * pstatus)
 38     [Inline Frame] combase.dll!SyncClientCallRetryContext::SendReceiveWithRetry(tagRPCOLEMESSAGE *)
 39     [Inline Frame] combase.dll!CSyncClientCall::SendReceiveInRetryContext(SyncClientCallRetryContext *)
 40     combase.dll!ClassicSTAThreadSendReceive(CSyncClientCall * pClientCall, tagRPCOLEMESSAGE * pMsg, unsigned long * pulStatus)
 41     combase.dll!CSyncClientCall::SendReceive(tagRPCOLEMESSAGE * pMessage, unsigned long * pulStatus)
 42     [Inline Frame] combase.dll!CClientChannel::SendReceive(tagRPCOLEMESSAGE *)
 43     combase.dll!NdrExtpProxySendReceive(void * pThis, _MIDL_STUB_MESSAGE * pStubMsg)
 44     rpcrt4.dll!_NdrClientCall2()
 45     combase.dll!ObjectStublessClient(void * ParamAddress, long Method)
 46     combase.dll!_ObjectStubless@0()
 47     msftedit.dll!CSpellerGlobalState::ForegroundSpellCheck(struct ISpellChecker *,unsigned short *,bool)
 48     msftedit.dll!CSpellerGlobalState::SpellCheck(struct ISpellChecker *,unsigned short *,bool,bool,unsigned long,bool)
 49     msftedit.dll!CSpellCheckerEngine::CheckRangeWithCtx(struct ISpellEnginePosition *,struct ISpellEnginePosition *,struct ISpellEnginePosition *,bool)
 50     msftedit.dll!CSpellCheckerEngine::SpellCheckAndAutocorrect(bool *,unsigned long,bool)
 51     msftedit.dll!CSpellChecker::Spellcheck(void)
 52     msftedit.dll!CSpellChecker::ScanAndUpdate(void)
 53     msftedit.dll!CGenUndoBuilder::~CGenUndoBuilder()
 54     msftedit.dll!CTxtRange::SetText2()
 55     msftedit.dll!CTSF30Base::OnTextUpdatingWorker()
 56     msftedit.dll!Microsoft::WRL::Details::DelegateArgTraits<long (__stdcall Windows::Foundation::ITypedEventHandler_impl<Windows::Foundation::Internal::AggregateType<Windows::UI::Text::Core::CoreTextEditContext *,Windows::UI::Text::Core::ICoreTextEditContext *>,Windows::Foundation::Internal::AggregateType<Windows::UI::Text::Core::CoreTextTextUpdatingEventArgs *,Windows::UI::Text::Core::ICoreTextTextUpdatingEventArgs *>>::*)(Windows::UI::Text::Core::ICoreTextEditContext *,Windows::UI::Text::Core::ICoreTextTextUpdatingEventArgs *)>::DelegateInvokeHelper<Windows::Foundation::ITypedEventHandler<Windows::UI::Text::Core::CoreTextEditContext *,Windows::UI::Text::Core::CoreTextTextUpdatingEventArgs *>,<lambda_954949c5830b0088dafa56babb0eecfa>,-1,Windows::UI::Text::Core::ICoreTextEditContext *,Windows::UI::Text::Core::ICoreTextTextUpdatingEventArgs *>::Invoke()
 57     Windows.UI.Core.TextInput.dll!Microsoft::WRL::InvokeTraits<-2>::InvokeDelegates<class <lambda_01228b047d095ba6977e9a543f5ec51b>,struct Windows::Foundation::ITypedEventHandler<class Windows::UI::Internal::Text::Core::CoreTextEditViewJunction *,class Windows::UI::Internal::Text::Core::ViewCompositionTerminatedEventArgs *> >(class <lambda_01228b047d095ba6977e9a543f5ec51b>,class Microsoft::WRL::Details::EventTargetArray *,class Microsoft::WRL::EventSource<struct Windows::Foundation::ITypedEventHandler<class Windows::UI::Internal::Text::Core::CoreTextEditViewJunction *,class Windows::UI::Internal::Text::Core::ViewCompositionTerminatedEventArgs *>,struct Microsoft::WRL::InvokeModeOptions<-2> > *)
 58     Windows.UI.Core.TextInput.dll!Microsoft::WRL::EventSource<struct Windows::Foundation::ITypedEventHandler<class Windows::UI::Internal::Text::Core::CoreTextSystemInputProcessor *,class Windows::UI::Internal::Text::Core::CoreTextInputKeyNotifiedArgs *>,struct Microsoft::WRL::InvokeModeOptions<-2> >::InvokeAll<struct Windows::UI::Internal::Text::Core::ICoreTextSystemInputProcessor *,struct Windows::UI::Internal::Text::Core::ICoreTextInputKeyNotifiedArgs *>(struct Windows::UI::Internal::Text::Core::ICoreTextSystemInputProcessor *,struct Windows::UI::Internal::Text::Core::ICoreTextInputKeyNotifiedArgs *)
 59     Windows.UI.Core.TextInput.dll!Windows::UI::Text::Core::CEditContext::ReplaceTextInternal(int,int,struct MsgString *,bool,int,int)
 60     Windows.UI.Core.TextInput.dll!Windows::UI::Text::Core::CEditContext::ReplaceText(int,int,struct MsgString *)
 61     msctf.dll!CTextChange::Execute()
 62     msctf.dll!CTextInputClientOwnerAdapter::_ExecuteOperation()
 63     msctf.dll!CTextInputClientOwnerAdapter::SetText(unsigned long,long,long,unsigned short const *,unsigned long,struct TS_TEXTCHANGE *)
 64     TextInputFramework.dll!CACPWrap::SetText(unsigned long,struct IAnchor *,struct IAnchor *,unsigned short const *,unsigned long)
 65     TextInputFramework.dll!CRange::_SetText(unsigned long,unsigned long,unsigned short const *,long)
 66     TextInputFramework.dll!CRange::SetText(unsigned long,unsigned long,unsigned short const *,long)
 67     IMETIP.DLL!CTipCompositionContext::SetText()
 68     IMETIP.DLL!CTipCompositionChunk::UpdateContext()
 69     IMETIP.DLL!CTipFnCompose::EsfnApplyInterimComposition(unsigned long,class CTipComposition *)
 70     IMETIP.DLL!CTipFnCompose::OnEditSession()
 71     IMETIP.DLL!CTipFnEditSessionHandler::_OnDoEditSession()
 72     IMETIP.DLL!Tsfutil::CTfEditSession::DoEditSession()
 73     TextInputFramework.dll!CInputContext::_DoEditSession(unsigned long,struct ITfEditSession *,unsigned long)
 74     TextInputFramework.dll!CInputContext::_EditSessionQiCallback(class CInputContext *,struct _TS_QUEUE_ITEM *,enum QiCallbackCode)
 75     TextInputFramework.dll!CInputContext::_DispatchQueueItem(struct _TS_QUEUE_ITEM *)
 76     TextInputFramework.dll!CInputContext::_EmptyLockQueue(unsigned long,int)
 77     TextInputFramework.dll!CInputContext::OnLockGranted(unsigned long)
 78     TextInputFramework.dll!CACPWrap::OnLockGranted(unsigned long)
 79     msctf.dll!CTextInputClientOwnerAdapter::_EnableCiceroSession()
 80     msctf.dll!CTextInputClientOwnerAdapter::RequestLock()
 81     TextInputFramework.dll!CACPWrap::RequestLock(unsigned long,long *)
 82     TextInputFramework.dll!SafeRequestLock(struct ITextStoreAnchor *,unsigned long,long *)
 83     TextInputFramework.dll!CInputContext::_QueueItem(struct _TS_QUEUE_ITEM *,int,long *)
 84     TextInputFramework.dll!CInputContext::RequestEditSession(unsigned long,struct ITfEditSession *,unsigned long,long *)
 85     IMETIP.DLL!CTipFnEditSessionHandler::InvokeInternal(enum __MIDL___MIDL_itf_tipfunc_0000_0009_0001,enum __MIDL___MIDL_itf_tipfunc_0000_0009_0002,struct ITipEditSessionProcedure *,struct IUnknown *,long *,unsigned long)
 86     IMETIP.DLL!CTipFnEditSessionHandler::Invoke(enum __MIDL___MIDL_itf_tipfunc_0000_0009_0001,enum __MIDL___MIDL_itf_tipfunc_0000_0009_0002,struct ITipEditSessionProcedure *,struct IUnknown *,long *)
 87     IMETIP.DLL!CTipFnCompose::OnApplyComposition(class CTipComposition *,int)
 88     IMETIP.DLL!CTipFnProductStringHandler::UpdateComposition()
 89     IMETIP.DLL!CTipFnProductStringHandler::_OnProductObjectChanged()
 90     IMETIP.DLL!Imeapiutil::CImeProductObjectChangeNotify::OnProductObjectChanged()
 91     IMJKAPI.DLL!CImeProductObject_JK::EndUpdateProductObject()
 92     imkrapi.dll!CImeCommonAPI_KOR_Desktop_V1::GenerateProductString(void)
 93     imkrapi.dll!CImeCommonAPI_KOR_Desktop_V1::RunHangulAutomata(struct __MIDL___MIDL_itf_imeapi_0000_0009_0001 const *)
 94     imkrapi.dll!CImeKeyEventHandler_KOR_Desktop_V1::ProcessKey(struct __MIDL___MIDL_itf_imeapi_0000_0009_0001 const *)
 95     imkrapi.dll!CImeKeyEventHandler_KOR_Desktop_V1::OnKeyDown(struct __MIDL___MIDL_itf_imeapi_0000_0009_0001 const *,int *)
 96     IMETIP.DLL!CTipFnKeyEventHandler::OnKeyDown()
 97     IMETIP.DLL!CTipContextEditorMgr::_OnKeyboardEvent()
 98     IMETIP.DLL!Tsfutil::CTfKeyEventSink::OnKeyDown()
 99     msctf.dll!CTip::OnKeyboardEvent(struct IInputContextPrivate *,enum KeyEventFlags,unsigned int,long,int *)
 100    msctf.dll!CThreadInputMgr::_CallKeyEventSink(unsigned long,struct IInputContextPrivate *,enum KeyEventFlags,unsigned int,long,int *)
 101    msctf.dll!CThreadInputMgr::_KeyStroke(enum KeyEventFlags,unsigned int,long,int *)
 102    msctf.dll!SYSTHREAD::OnKeyboardEvent(unsigned int,long,bool)
 103    msctf.dll!_TF_Notify@12()
 104    user32.dll!CtfHookProcWorker(int,unsigned int,long,unsigned long)
 105    user32.dll!CallHookWithSEH()
 106    user32.dll!___fnHkINDWORD@4()
 107    ntdll.dll!_KiUserCallbackDispatcher@12()
 108    XamlIslandsApp.exe!WinMain(HINSTANCE__ * hInstance, HINSTANCE__ * hPrevInstance, char * lpCmdLine, int nCmdShow)
 109    [External Code]`

Steps to reproduce the bug

Configure Korean keyboard layout in “Language settings”. I used the default settings: input method “Microsoft IME”, hardware keyboard type “2 Beolsik” (I use a standard UK hardware keyboard without Korean language support).
Start XamlIslandsApp from https://github.com/ilitosh/XamlPlayground. (This is just a basic XAML app with a basic Textbox.) Important to have Spellcheck enabled. This is where the TextBox is configured.
Switch to Korean: and toggle English/Hangul tooggle to Hangul (see the image below). Type in Korean until it crashes. I used this AutoHotkey script which imitates typing, and reliably reproduces the crash most of the time.