With thousands of extensions, themes, personas, user styles, and Greasemonkey scripts, you may think there is no room for even further customization, however Personas Expression is here to prove you wrong.

As its name suggests it adds a new level of customization with options to change the text color, add a transparent layer over the toolbars with specified texture and color, and making the foreground elements transparent, all from a new sidebar accessible from the status bar or the View menu.

Get Personas Expression from Mozilla Add-ons now.