Another thing that has the potential to be one of those "oops I guess human error just launched all the nuclear missiles of the world" type UX bugs is that Firefox is a crashy pile of poo on my Linux machine and then it gives me the dialog box that lets me restart it, but then it restarts with the wrong Profile so then I am doing stuff as some other random/arbitrary user but I don't realize it because I blithely assumed it would have restarted with the same context. Impressive!