[Bug 21615] New: Steam: Windows are confined to a certain area

http://bugs.winehq.org/show_bug.cgi?id=21615

Summary: Steam: Windows are confined to a certain area
           Product: Wine
           Version: 1.1.38
          Platform: x86-64
        OS/Version: Linux
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: -unknown
        AssignedTo: [e-mail]
        ReportedBy: [e-mail]

Created an attachment (id=26084)
 --> (http://bugs.winehq.org/attachment.cgi?id=26084)
Window is fully visible where it spawned

I'm using wine 1.1.38 on Gentoo amd64.
I noticed that when I open a chat window for steam, if I try to move it the
window becomes partially "hidden behind the background".

It's only fully visible where it spawned.

I'm uploading some screenshots to illustrate the bug.