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Personas are free, easy-to-install "skins" for Firefox. Personas Plus extends that built-in functionality to give you even more control and easier access to new, popular, and your own favorite Personas.
Help make Firefox better. The Add-on Compatibility Reporter enables you to report if the Firefox add-ons that you're using are working properly.
Help us make Firefox better by joining our structured user studies! No need to download this add-on if you are running Firefox 4 beta, - you are already a part of the team!
An extension that allows for the use of dynamic commands in Firefox.
A maintained version can be installed via: https://bitbucket.org/satyr/ubiquity/downloads/tip.xpi
Jetpack Prototype is an experiment in making it easy to build Firefox add-ons using common web technologies.