ID:2412998
 
Resolved
Changing icon frames resulted in the modify flag being set incorrectly, so closing the file would prompt to save it or abandon changes even though no changes were made.
BYOND Version:512.1456
Operating System:Windows 7 Pro 64-bit
Web Browser:Chrome 70.0.3538.102
Applies to:Dream Maker
Status: Resolved (512.1457)

This issue has been resolved.
Open an .dmi file, open an state, click a different frame other than the default, don't do anything on the canvas, return. The file will be set as modified even if you didn't change anything, and when you close the tab it'll ask if you don't wish to save.
Lummox JR resolved issue with message:
Changing icon frames resulted in the modify flag being set incorrectly, so closing the file would prompt to save it or abandon changes even though no changes were made.