[Bug 55782] New: System.Windows.Forms expects CreateActCtx() to succeed with truncated ACTCTX structure

[WineHQ Bugzilla]

https://bugs.winehq.org/show_bug.cgi?id=55782

Bug ID: 55782
           Summary: System.Windows.Forms expects CreateActCtx() to succeed
                    with truncated ACTCTX structure
           Product: Wine
           Version: 8.17
          Hardware: x86-64
                OS: Linux
            Status: NEW
          Keywords: source, testcase
          Severity: normal
          Priority: P2
         Component: kernel32
          Assignee: [e-mail]
          Reporter: [e-mail]
      Distribution: ---

Major versions of .Net installed by winetricks (including 4.0, 4.52, 4.72, 4.8)
are affected by this bug.

According to
https://github.com/dotnet/winforms/blob/4.8/src/Common/src/UnsafeNativeMetho...
internal definition of ACTCTX is missing hModule field, and as a result cbSize
doesn't match the expectations of Wine's CreateActCtx() implementation
https://github.com/dotnet/winforms/blob/4.8/src/Common/src/UnsafeNativeMetho...

The following MR aims to fix this bug:
https://gitlab.winehq.org/wine/wine/-/merge_requests/3839