The nightly builds of Firefox 3.1 have added a significant improvement to the session restore dialog you normally see after a crashed browsing session. The upshot: Rather than displaying a modal dialog that requires you to restore your old session or start from scratch, Firefox will display an about:sessionrestore tab in which you can selectively disable any tab or window from the previous session before you continue with the restore. If you suspect any web site of causing your crash, the option to disable it from the session restore is a real boon. It may not be as good as Google Chrome's per-tab process isolation—which ensures that no single tab can bring down any other—but it's still better than finding yourself with a choice between a crash loop or losing your saved session altogether. Thanks David!
turn the Session Restore prompt into an error page [Bugzilla]