GIMP 2.10 claims that it can (try to) recover images upon restarting after a crash.
However, restarting the PAF version gives a message saying that "GIMP was not closed properly on the last time it ran and needs to clean up"
(or something like that).
So, I'm guessing that your standard clean up is preventing the file recovery.
BACKGROUND INFO:
About once every 5 weeks; GIMP just closes on me. No error message or anything. It just closes.
Today it closed on me for the second time in 2 weeks. And it closed on a trivial command... "changing fussy paint brushes".
(GIMP 2.10-8 on Win 7 Pro 64bit)
MEMOS:
If I knew where the files were stored; hopefully I can manually recover them.
Past versions of GIMP (when installed locally) stored its files in %AppData% subdirectories.
I have looked in %TEMP%; %APPDATA%; C:\PortableApps\GIMPPortable\*
(but didn't see anything. ...although may be I just missed them)
Like most apps, GIMP Portable uses a contained TEMP directory that is designed to be wiped on close. If GIMP crashes, the launcher will then clean up the TEMP files on exit. If you're seeing the above error, that means that the GIMP Launcher was also somehow crashed on your system. It's possible this was through an unsafe eject or because GIMP itself crashed its UI but the EXE was still running preventing Windows from closing down. I'd check your drive to be sure there are no errors. If GIMP is this unstable on your system that you regularly need to recover files, I would suggest using the locally installed version for now until you can determine what's going on.
Sometimes, the impossible can become possible, if you're awesome!