Latest version of FF is installed already. The only thing is that my menu bar had disappeared with one of the latest automatic updates, so I left it as I wasn't really missing it. Today I went trying to determine the version installed, and got it turned back on, and I also checked for plugins installed. Ther was one I didn't recognize as needed (something about automatically destroying gamesites, or whatever), so I removed it and also disable a skype dialer (that I never use). FF restarted and now it seems fine...return key does as intended.