Why is TOPMOST not included in MessageBoxOptions?

[KevinKrueger]

(MessageBoxOptions)0x40000);  // MB_TOPMOST

MessageBox.Show("xxx", "xx", MessageBoxButtons.OK, MessageBoxIcon.Warning, MessageBoxDefaultButton.Button1, (MessageBoxOptions)0x40000);

[EgorBo]

https://github.com/dotnet/winforms is the correct place to ask this question, MessageBox is not part of .NET runtime/BCL

[jeffschwMSFT]

@merriemcgaw can you help with the transfer?