Does this happen when you run Firefox with a new profile? This can help determine if there is an error in firefox, or if the problem is caused by your specific combination of add-ons and settings. Instructions for doing this can be found at https://wiki.ubuntu.com/MozillaTeam/Bugs.
Also, when Firefox crashed, did you submit a crash report to Mozilla? Thanks! ** 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/833346 Title: launch failure, slow loading, lock computer Status in “firefox” package in Ubuntu: Incomplete Bug description: Firefoxx updated, restarted firefox, firefox will not launch, locks computer, if it does start runs VERY slowly. system updater shows no updates needed. computer updated DAILY , firefox continues to crash while running. restarting firefox will not launch, restart computer and firefox still won't launch. Several computer restarts required before FF will launch but will crash ProblemType: Bug DistroRelease: Ubuntu 11.04 Package: firefox 6.0+build1+nobinonly-0ubuntu0.11.04.1 ProcVersionSignature: Ubuntu 2.6.38-11.48-generic 2.6.38.8 Uname: Linux 2.6.38-11-generic i686 Architecture: i386 Date: Wed Aug 24 16:26:51 2011 FirefoxPackages: firefox 6.0+build1+nobinonly-0ubuntu0.11.04.1 flashplugin-installer 10.3.183.4ubuntu0.11.04.1 adobe-flashplugin N/A icedtea-plugin 1.1.1-0ubuntu1~11.04.1 InstallationMedia: Ubuntu-Netbook 10.04 "Lucid Lynx" - Release i386 (20100429.4) ProcEnviron: LANGUAGE=en_US:en LANG=en_US.UTF-8 SHELL=/bin/bash SourcePackage: firefox UpgradeStatus: Upgraded to natty on 2011-05-08 (108 days ago) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/firefox/+bug/833346/+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