Giorgio Maone, author of NoScript, one of the most popular Firefox extensions, has blogged about several full session crashes experimented by NoScript users on just released Ubuntu 10.04, due to a bug in the xorg-server package.
According to Giorgio, there is already a patch for the bug but it’s not being pushed as an automatic update yet.
To get it, Ubuntu users must run the following command:
sudo add-apt-repository ppa:bryceharrington/purple && apt-get update && apt-get upgrade
Giorgio also explains that NoScript interaction is just one of many ways a user could hit the bug. A crash can happen even without NoScript installed, reportedly.