I've been using Windows 8 for 5 months with minimal problems. This morning my internet screen suddenly changed--no idea what I did-- and left me with no menu bars or tool bars. Just a full screen with google icon and box in center of page. If i push to top, I get the tab for the open page where I can type in address. If I push to bottom, I get a handful of icons. By click on the help icon I get to a normal looking screen. How do I get to the normal opening screen which allows me to see all of the bars and the icon for windows?
Make sure that you do not run Firefox in full screen mode (press F11 or Fn + F11 to toggle; Mac: command+Shift+F).
If you are in full screen mode then hover the mouse to the top to make the Navigation Toolbar and Tab bar appear.
Click the Maximize button (top right corner of the Navigation Toolbar) to leave full screen mode or right click empty space on a toolbar and choose "Exit Full Screen Mode" or press the F11 key.