If you are on an unsaved file tab and choose "Close all but this", before closing all the other tabs it asks you if you want to Save the file you're working on before closing so you don't lose the changes ...... except, you're not closing that file. You can click "No" and it leaves the file open as expected, but shouldn't be prompting for save when you're explicitly not closing it.

yea, i have notice that too, the first time i did it i was like, i did not want to close this file. nothing major just a little annoying.