I have a student chromebook that will not access fullscreen mode. When you turn off the computer it will temporarily go to normal mode but it automatically reverts back. There are not buttons to exit. The only thing that I see are arrow icons, a house icon, and a reload button, and the only one of the icons that I can click on are the arrow buttons. I have tried hitting esc, toggle buttons, etc. but nothing works. Is this a setting that needs to be fixed?