Option to close an orphan window or tab with backspace
 

I'd like to be able to close a window, or a tab, that's newly created (so that 'back' doesn't do anything) by hitting backspace. This makes sense, because when a link opens in a new window or tab, what you'd want when you hit backspace is what you want when no new window or tab is opened: you want to return to the previous page, the one that the link you followed was on. Should be an optional thing, though, as it's probably confusing to some people.