Well that’s no good! I haven’t been able to reproduce this locally with the same windows version.
Does it crash silently to the desktop or do you see an error message on crash? Do you see any errors in the logs? (located at %appdata%/Deepdwn/logs).
Does it occur with an empty document?
Does it occur when booting in safe mode?
Does it occur when using the File Menu > Export > PDF option? How about when opening the preview window and clicking the save icon?
Does it happen when exporting as HTML?
Could you try renaming the Deepdwn settings folder (%appdata%/Deepdwn) and seeing if it occurs? You can rename it back afterward to restore your settings.
I do see a crash when the print spooler service is stopped in windows, and probably related to this issue as well: https://itch.io/t/4120673/crashes-when-using-atlasos
Could that be the case for you?