Hello all, I have a very strange problem.

I'm trying to write a script that will force close several applications. I saved the script in /usr/local/bin and set up a keyboard shortcut to it in XFCE. The script works, but only if the application is not fullscreen:

Code:
#!/bin/bash
# init

killall vlc
killall zsnes
killall frozen-bubble
I don't understand why fullscreen would matter. Is there any way to set up a keyboard shortcut to run this script regardless of whether or not an application is running full screen?