[Bug 44597] New:=?UTF-8?Q?=20Window=20rendering=20com?= pletely breaks after interacting with the “Desktop Integration” section of winecfg with enabled GTK3 themeing

https://bugs.winehq.org/show_bug.cgi?id=44597

Bug ID: 44597
           Summary: Window rendering completely breaks after interacting
                    with the “Desktop Integration” section of winecfg with
                    enabled GTK3 themeing
           Product: Wine-staging
           Version: unspecified
          Hardware: x86
                OS: Linux
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: -unknown
          Assignee: [e-mail]
          Reporter: [e-mail]
                CC: [e-mail], [e-mail],
                    [e-mail]
      Distribution: ---

Created attachment 60584
  --> https://bugs.winehq.org/attachment.cgi?id=60584
Changes in HKCU registry

# Background & Steps to reproduce

Window rendering will show bizare artifacts, up to becoming totally useless
(tiny transparent window frames that cannot be interacted with), after
following the below steps:

1. In WINE staging enable GTK3 themeing
 2. Open `winecfg` again (things should be themed now)
 3. Select the “desktop integration” tab
 4. Change the “theme” from “GTK-3” to “(No Theme)” and click “Apply”
 5. Do the above two times for noticable rendering issues and crashes
 6. Do the above three (or more) times to break *any window rendering in WINE*
(see attachment 2)

# Underlying issue

I'm not exactly sure what `winecfg` happens to do here, but it somehow manages
to calculate and store some completely wrong values for several entries inside
the

HKEY_CURRENT_USER\Control Panel\Desktop\WindowMetrics

registry key (see attachment 1) that then result in this behaviour.

# Workaround

Open `${WINEPREFIX}/user.reg` in a text editor and delete the entire

HKEY_CURRENT_USER\Control Panel\Desktop\WindowMetrics

registry key section before launching WINE again.