Add 'restart' to file menu. See bug#336050. In Firefox 2.0 there are situations where you want to restart (eg changing theme) but there is no restart button, so you don't get a saved session. This makes restart visible always.
Answering some comments: this is purely a bug workaround, there'll be no more GUI since this ext will die when the bug is fixed. I wasn't aware of 'Restart Firefox' before I wrote this, but there are differences: 'Restart Firefox' only reopens tabs at the moment, 'Restarter' uses FF2 saved sessions and reopens all tabs and windows. RF is maintained for more versions though.