Hot on the heals of the Firefox 3.7 interface mock-ups, Firefox 4.0 mock-up designs have surfaced.
While the new Windows interface looks similar to that of Firefox 3.7, there are some slight differences, including an in-line refresh and stop button.
Two separate designs have been proposed, one with tabs above the address bar, and one with the tabs below the address bar as is currently the case. More screen shots are available after the jump.
