FF telling me it needs to restart, refusing to open a new tab, happens all the time for me, at mostly annoying times such as in the middle of a session while logged in. Doesn't have anything to do with the number of open tabs, but is due to FF having downloaded updates. Maybe it's a config option? Anyway, I'm wondering why FF needs restarting, and in combination with the frequency this happens (at least once a month), I'm questioning the architecture behind this - after all I don't want my browser to update more often and consume more download bytes than the content I'm after, and I'm not looking forward to a web/web browser that needs constant updates after 30 years sorry.