[Bug 13683] Ultima IX: Mouse pointer missing when reading books, under inventory

https://bugs.winehq.org/show_bug.cgi?id=13683

--- Comment #44 from Christopher Thielen  ---
I'm not sure if this is the relevant difference but I found one difference
between Wine and Windows XP regarding a WM_CAPTURECHANGED message where lParam
== hWnd.

If you compile a basic Win32 app and call SetCapture() before the main message
processing loop, Windows will send you a WM_CAPTURECHANGED message with your
own hwnd as the lParam while Wine will send nothing.

I'll attach an example.