[nullindividual]

It's actually been fixed. I didn't, and neither did OP, read far enough through the SO thread linked in the GitHub issue.

Fix was previously included in https://support.microsoft.com/en-us/topic/june-27-2017-kb402....

> Addressed issue (Error 0x7F) with Windows Forms (WinForms) that causes the system to crash after upgrading to the Creators Update.

[afrisch]

It has been fixed but a similar problem (with the same repro case) reappeared with a recent Windows update, only now when closing the popup.