http://bugs.winehq.org/show_bug.cgi?id=24579
--- Comment #48 from Gediminas Jakutis vinislentoje@gmail.com 2012-11-03 18:20:08 CDT --- Although this is fixed and works well for situations when NOT using a virtual desktop, this bug persists when in a virtual desktop. When in a virtual desktop, steam has all the symptoms of this bug: moving/resizing a window moves/resizes it doubly. /* I never saw this to be fixed for virtual desktops, but was hoping it will be fixed soon after it got fixed for no-virtual-desktop situations, and hesitated to report. Sorry about that. */
I last tested it on the currently latest git [wine-1.5.16-159-g561e46c]
TL;DR: This bug is still present on virtual desktops.