https://learn.microsoft.com/en-us/windows/win32/api/msctf/nf-msctf-itflanguageprofilenotifysink-onlanguagechanged?redirectedfrom=MSDN
ITfLanguageProfileNotifySink::OnLanguageChanged (msctf.h) - Win32 apps | Microsoft Learn
ITfLanguageProfileNotifySink::OnLanguageChanged method
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