Full screen mode is difficult to get into. Most of the time I'll only get a blank black box on the screen with it claiming to be Full Screen. Exiting full screen keeps a black square on the screen. (Although sometimes Full screen has no problem and works fine. But it is rare). You can still click on the menu buttons and such once full screen is closed, but you have no idea what you are doing due to the window being blank, black box.
What I expected to happen was...:
Click F11 or (if set to start with full screen) and Full screen appears like normal.

What actually happened was...:
Full screen doesn't happen 95% of the time. It leaves a blank black box and I have to push F11 to exit the non-existant full screen, then close the window.

Steps to Reproduce:
1. Run Minecraft
2. See the Mojang logo
3. Black box appears instead of Minecraft in full screen.

(In the screen shots, please note the top left corner. The first one is Full screen, the second is after full screen was exited.)