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NativeWindowViews::SetForwardMouseMessages() installs a low-level mouse hook when mouse forwarding begins and unhooks it once no window needs forwarding. The previous code reset the shared `mouse_hook_` handle to `nullptr` unconditionally after calling UnhookWindowsHookEx, even when the unhook call failed. When unhooking fails, the hook is still installed in the system. Because `mouse_hook_` is nulled out anyway, the next call to SetForwardMouseMessages(true) evaluates `if (!mouse_hook_)` as true and installs a second, duplicate hook via SetWindowsHookEx, so every mouse message is processed by MouseHookProc multiple times. Check the return value of UnhookWindowsHookEx and only null the handle on success. When the call fails, leave `mouse_hook_` pointing at the existing hook so the next activation reuses it rather than stacking a new one on top, and log the failure via PLOG to surface the underlying Windows error. Fixes: #51064 Signed-off-by: Asish Kumar <officialasishkumar@gmail.com> Co-authored-by: Asish Kumar <officialasishkumar@gmail.com>
Signed-off-by: Asish Kumar <officialasishkumar@gmail.com> Co-authored-by: Asish Kumar <officialasishkumar@gmail.com>
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Backport of #51098
See that PR for details.
Notes: Fixed an issue on Windows where a transient
UnhookWindowsHookExfailure insetIgnoreMouseEvents(true, { forward: true })teardown could cause duplicate low-level mouse hooks to be installed on the next activation.