[Bug 48321] New: Drawing issue with overlapping windows on Kontakt

[WineHQ Bugzilla]

https://bugs.winehq.org/show_bug.cgi?id=48321

Bug ID: 48321
           Summary: Drawing issue with overlapping windows on Kontakt
           Product: Wine
           Version: 4.21
          Hardware: x86-64
                OS: Linux
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: -unknown
          Assignee: [e-mail]
          Reporter: [e-mail]
      Distribution: ---

Created attachment 66039
  --> https://bugs.winehq.org/attachment.cgi?id=66039
Weird drawing issue

Hi
I have this weird drawing issue with this software: if I open the library
manager the content of the new window is not visible until I move it out of the
main window of the plugin. The same happens with the sub windows that are
opened from there. 
I am launching this as a plugin through Carla-Patchbay and the wine bridges
from any software that supports it, but I am sure it happens even launching the
standalone version.
This probably can affect other software and does not happen on Windows.
Here you can find a screenshot of the issue as attachment.