When fullscreen, it would be useful to be able to chose to only see the rendered area, without the tabs, bookmarks, address bar etc. Safari can do this when "Always show toolbar in full screen" is disabled in the View menu. It's great for more content on the screen, specially on a smaller screen like a laptop.
Hmm, it does work that way on Windows. I wonder why Mac works differently?
If you right-click (one button: Ctrl+click) a blank area of the tabs bar, do you get this option:
That is a bit difficult to find...