Thank you for reporting this to Ubuntu. Sometimes Firefox extensions can conflict. Could you please try this with a new profile and see if the problem still exists? You do not need to delete your old profile to test. If this helps, you might want to try to disable all your extensions and re-enable them one by one until you find the problematic one.
You can start the profile manager with the following command: firefox -ProfileManager ** Changed in: firefox (Ubuntu) Status: New => Incomplete -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to firefox in Ubuntu. https://bugs.launchpad.net/bugs/985408 Title: Firefox 11.0 freeze/crash! Status in “firefox” package in Ubuntu: Incomplete Bug description: Firefox uses 225MB of RAM after 10min of uptime, then freezes the whole system. On occasions, it crashes every 2-5 mins. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/firefox/+bug/985408/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp