Oh crap, Firefox just crashed. With 50 tabs open. You restart it, praying that it doesn’t choke as it tries to reload all 50 at once and that the problematic tab – if there was one – doesn’t force you kill Firefox.exe from Task Manager.
In the latest Nightly builds, that’s less of a problem. Now, when Firefox restarts, it loads all tabs except the most recently focused one with their titles solely. The most recently focused tab is loaded completely. Only when you actually select another restored tab does Firefox actually load its contents. Genius, no? Hello faster and more stable session recovery. I suppose the only caveat is that if the most recently focused tab happens to be the problematic one, you might be in the same position as described at the outset.
It’s not exactly the “each tab in a separate process” advancement that Chrome has had from the outset, IE already implemented and Mozilla is still working on, but it’s a much appreciated improvement.