I've seen this a few times but think I did it myself while saving the game. After clicking on save game and then while double clicking on the file to save over the top of, one of the clicks seems to register sometimes on the options menu that appears after the save menu goes away. I've definitely changed resolution this way before which is certainly one of the things that needs a restart. Think I've possibly clicked other options on that screen as well, but not positive as I don't recall exactly which settings I'm using. Should probably write that down so I can keep track.