Firefox 6 just made its way on my Ubuntu installation. That broke Capybara tests that use selenium-webdriver with the annoying unable to obtain stable firefox connection in 60 seconds _error. Looks like support for Firefox 6 has just been committed and there’s nothing released. _So hold your upgrades!
If you’re like me and just hit update, downgrading to an older version of Firefox is going to be non-trivial. The Firefox people make it super hard by hiding older versions and not versioning packages. They also make it particularly hard to run multiple versions, at least in my experience. I finally managed to go back to 3.6 with these instructions and in the process learned something about _apt-cache policy _that can be tweaked to prefer distribution sources. Now, where can I find a distribution of Firefox 4 or 5 and how do I install it?