Crash when exiting fullscreen mode

After playing Minecraft in fullscreen mode(F11) I wanted to get out of fullscreen and do something else, but instead after I got out of fullscreen my Minecraft window had random coloured pixels, and I crashed, which ended up causing my whole computer to crash...

What I expected to happen was...:
Minecraft to get out of fullscreen mode.

What actually happened was...:
Minecraft, and my computer crashed.

Steps to Reproduce:
1. Launch Minecraft.
2. Go into fullscreen mode.
3. Exit fullscreen mode.
4.Minecraft crashes.