Well, there is auto-filling in the sense that if you press Ctrl-Shift-L (at least on the browser extension), it will find the user/pass fields and fill them in

Well, there is auto-filling in the sense that if you press Ctrl-Shift-L (at least on the browser extension), it will find the user/pass fields and fill them in for you. But it requires you to press the shortcut, so it doesn’t do so unprompted.