blotunga: Hmm, I have no such buttons could be because of the Barefoot Essentials?
I've never used Barefoot, I like just plain browsing, even if it is a pain sometimes. I'm on Firefox 27.0.1. I have noticed the button only shows up if I have something that needs updating, otherwise it disappears. I've actually gotten into the bad habit of leaving a game not-updated just so it stays around. :)
Edit:
Added screenshot pic.