[Bug 27355] New: SumatraPDF 1.6: tooltips leave black rectangles when disappearing

http://bugs.winehq.org/show_bug.cgi?id=27355

Summary: SumatraPDF 1.6: tooltips leave black rectangles when
                    disappearing
           Product: Wine
           Version: 1.3.21
          Platform: x86-64
        OS/Version: Linux
            Status: NEW
          Severity: normal
          Priority: P2
         Component: -unknown
        AssignedTo: [e-mail]
        ReportedBy: [e-mail]

Hover a toolbar button, showing the tooltip, then move the mouse elsewhere.

The tooltip disappears, but a black rectangle remains instead (covering the
whole tooltip display area)