Ah well. No idea about Mac. Might be different there for all I know, but the Windows-version has been like that since FF 4, at least when the window is maximize

Ah well. No idea about Mac. Might be different there for all I know, but the Windows-version has been like that since FF 4, at least when the window is maximized. When not maximized it sort-of looks like in the linked screenshot. Running the latest "UX-builds", I can see that it now has the maximized-behvaiour for all Window-states, so you are right in there being some changes.