Clean Links aims to help you convert obfuscated or nested links into genuine, clean and nice-looking links.
You can disable the Clean Links add-on anytime by clicking the toolbar icon, that becomes black/greyed when is turned off.
When some links are converted, the icon will change its color and you will be able to mouse-over to open its pop-up where you can see the number of converted links on the current website.
Note: The Clean Links add-on is cross-platform and it works on Mac OS X, Windows and Linux.