I run XFCE 14.04 through Crouton on Linux. The first thing I install after a fresh Linux install is Guake Terminal. Pressing F12 brings down an overly terminal that is really handy to use.
But as you can see above the transparency doesn’t work properly out of the box with a fresh Linux install.
So to enable that you must do the following:
1. Open up Settings and click on Window Manager Tweaks.
3. Now restart your computer, and the alpha transparency will be working now!.