Here you'll find the archived PrefBar project. PrefBar was an "All In One" Add-on for Mozilla browsers which has been replaced by some Replacement Add-ons
PrefBar started as a simple toolbar to get easy access to common preferences like Javascript, Flash, the proxy used for web access, ... Over the time, PrefBar got further developed to be a container for nearly everything, that can be placed on a button, checkbox or menulist.
PrefBar allowed stuff like "immediate installation without browser restart" or "customizable toolbar" long before Firefox had those built-in. With the ongoing Firefox development, the button management, provided by PrefBar, got more and more obsolete. Nowadays it is much easier to do the same with individual Add-ons for each task.
The source code is directly in this repository. I've added all the contributed buttons to this repository, too, so all the sourcecode is in one place.
Installation packages can be found in Releases
You'll find the HowTos and contributed button list in the project Wiki
There is still a Forum thread around PrefBar which I visit occasionally mozillaZine Forum thread