In Firefox, cmd+shift+n is "undo close window" and has been for a very long time. Possibly even predating private browsing mode... Other browsers don't have t

In Firefox, cmd+shift+n is "undo close window" and has been for a very long time. Possibly even predating private browsing mode... Other browsers don't have to have "undo close window" as a feature at all, so had the shortcut free for private browsing.