found in 1.12.2781.0 Bug Bash on 10/5/2021

REPRO:
1. Open the Terminal
2. Edit the json so it's invalid (delete a comma in the settings)
3. Move the window, so the warning dialog dismisses itself.
4. Edit the settings again. Leave it invalid. Add a newline
5. Notice, no dialog (ooooooooooh)
6. Now try to close the window, that won't work

This certainly regressed when I added support for dismissing that dialog when the window moved.