Thanks for the downvote, whomever. I always consider switching to Firefox, as I think Chrome needs competition, but Firefox has just never been up to par in usability (especially developer usability) whenever I've tried to switch. Things like "losing your work" for no good reason (don't Firefox have "Re-open closed Window"?) is just another thing I would add to the list of reasons not to switch, so feel free to clarify.
> (regardless of whether you have automatic session restore enabled for restart).
It also already has an optional check if you want to close a window ("you're closing a window with 10 tabs. sure?"), and a list of recently closed windows to restore.
I interpreted the change as if it would always show the quit warning regardless of any settings, since the warning popup is not exactly a new feature. Some more context helped clarify.