In May, Mozilla Labs vice president Chris Beard developed Personas, an experimental Firefox add-on for lightweight theming. The add-on makes it possible to apply custom artwork to the Firefox chrome, including the toolbars, tabs, and status bar. The addon is compatible with Firefox on all three major platforms.

The Personas addon started out as Beard's personal project, but has now found a new home at Mozilla Labs and has undergone a major rewrite that is compatible with the latest Firefox 3 beta. Beard says that Personas will become the starting point for experiments in dynamic personalization that Mozilla Labs will pursue in an effort to provide users with a richer browsing experience.

In the latest version of Personas, themes are automatically loaded directly from a JSON feed and are accessible through a menu that is embedded in the left-hand side of the status bar. All of the content is loaded from remote locations and the styling changes are applied dynamically without the need for restarting the browser.

Mozilla Labs is actively developing a new API that will enable artists to submit content for inclusion in the feed. According to Beard, artists will be able to use any technologies that are supported in a web page, including HTML, CSS, images, JavaScript, SVG, and the Canvas element. This opens the door for rich skinning with very low barriers to entry.

I probably won't use Personas much myself since I greatly prefer the unadulterated GTK look in Firefox 3, but the addon is very intriguing from a technical standpoint. The way that Personas takes Firefox's Internet capabilities and leverages theme to bring dynamic content to the Firefox chrome layer is very creative and it reflects a lot of possibilities that I had never previously considered.