Tried that, making sure i only had the latest version and it didn't work.

I unnistalled everything in the game's folder, in the %appdata% folder, in the itch app. I kept my old saves and persistent files elswhere so it didn't interfere and didn't put them in the game's folder after freshly installing the game again. I tried to make a new save and press "suppr" (or 'delete' in english cuz i'm french lol) and it gave me the same result ; i still can't delete saves in-game.

I don't know if this happens only to me but it's not really an issue since i can delete the saves directly in the game's and %appdata%'s RenPy folder, only a very tiny minor inconvenience.

Thank you for you time anyway and have a good day :)