https://bugs.winehq.org/show_bug.cgi?id=44504
--- Comment #6 from Henri Verbeet hverbeet@gmail.com --- Created attachment 60519 --> https://bugs.winehq.org/attachment.cgi?id=60519 patch
(In reply to Henri Verbeet from comment #5)
As for the regression though, does just restoring the XFlush() in X11DRV_ExtEscape() also restore the old behaviour for you?
I.e., does the attached patch help?