This is probably more a feature request than a question but I didn't know where to post this. When I open Firefox 48.0 in Mac OS X (10.11.6) full screen mode and put the cursor to the top of the screen the system menu bar and the app title bar both move down over the tab bar of the browser and get in the way. This is annoying because when trying to use the tab bar it is common for it to be obscured by the menu bar opening when the cursor is at the top of the screen. Firefox should behave in the same way that Safari and Opera do in that when you move the cursor to the very top of the screen all the interface (tab bar, address bar etc) at the top of the screen moves down to accommodate the system menu bar and the title bar of the app. Thanks