I switched back to Firefox from Chrome after two years because of pentadactyl. vim bindings and a command mode for my browser? Yes please.<p>Unfortunately pentadactyl proved to be not quite stable enough. Commands would intermittently fail and strange bugs kept popping up.<p>I looked around and found the older, but supposedly more stable, vimperator project. It's 100% compatible with my usage of pentadactyl (including fun things like remapping commands and keyword bookmarklets) and has been rock solid.