Full screen mode
You can use the Full Screen Mode button (between the online help button and the admin menu) to toggle full screen mode. In full screen mode the GUI menu and header are hidden the full browser window is taken up by the current GUI page. You can select the Exit Full Screen mode any time to return to the normal GUI arrangement.
TBC the GUI menu is hidden to the left of the screen. You have to click on the vertical bar to show the menu.