http://bugs.winehq.org/show_bug.cgi?id=27779
--- Comment #68 from Joel "iLag" Hammond ilagdoesntcheckthisemail@gmail.com 2011-09-10 16:11:31 CDT --- With WINEDEBUG="-all,trace+cursor", I discovered that the following line was constantly being called by Steam.exe, (albeit with a different end number each time I started up Steam): trace:cursor:SetCursor 0x2002a This occurs regardless of virtual desktop and fullscreen autocapture settings. However, when virtual desktop is on and fullscreen autocapture is off, SetCursor appears to ignore calls made to it by Steam.exe, at least when a fullscreen game is open on the same virtual desktop. If someone can figure out why this is, then progress can be made on fixing this bug.
A possible hack solution would be to check if the window of the process which calls SetCursor has focus, and if not, return.