https://bugs.winehq.org/show_bug.cgi?id=27814
--- Comment #12 from Ken Thomases ken@codeweavers.com --- This problem still exists for me on OS X, too. Plain Wine. (If you're using the tip from this morning, you'll need http://source.winehq.org/patches/data/108886 to fix a crash.) Affects both the Mac driver and the X11 driver.
In my testing, it was often the case that moving the mouse was not enough to cause the menu animation to proceed. When this happened, switching away with Command-Tab would allow the animation to complete. This happened more often with the Mac driver than the X11 driver, but did affect both.
Béla, would you be willing to do a "reverse" bisect, where you hunt which commit fixed it for you?