[init2null]

That's a rude and somewhat inaccurate response.

Photoshop has autosave that works well, even for files with hundreds of layers, so it can be done. That being said, I can see that it's less useful when someone chooses not to save.

As for export, a single-layer file should be considered saved when one exports to lossless. A multi-layer file needs a different prompt, and I note Gimp has that now. It flags the file as "Exported to xxxxxx.png" in the Quit dialog.

[prmoustache]

autosave is useful for a file format of working files, like psd if non destructive changes are supported. But it would be stupid for exported end result format like jpeg, png, webp or pdf where changes cannot be recorded.