
Log out of the manager and log back in. If that doesn’t work log out, re-run the installer in upgrade mode, then log back in.
Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.8.1.3) Gecko/20070324 BonEcho/2.0.0.3
Sounds like a corrupt Fx or an incompatible Fx extension.