I have the same problem. Running Ubuntu 14.04 with Compiz. Java version: 1.8.0_25. When I press any media key while in fullscreen in Minecraft 1.8.1, it exits fullscreen and vanishes. Mouseclicks don't work and i have to do Ctrl+Alt+F1 and kill the java process. If I exit fullscreen first, I can use the media buttons, but it's annoying to do that every time I want to adjust the volume.
Evan Straw
I have the same problem. Running Ubuntu 14.04 with Compiz. Java version: 1.8.0_25. When I press any media key while in fullscreen in Minecraft 1.8.1, it exits fullscreen and vanishes. Mouseclicks don't work and i have to do Ctrl+Alt+F1 and kill the java process. If I exit fullscreen first, I can use the media buttons, but it's annoying to do that every time I want to adjust the volume.