Mozilla released Firefox 3.6 beta 1 on Friday, October 30, 2009. Firefox 3.6 Beta 1 is now available for download. This beta version of the next version of Firefox is built on the Gecko 1.9.2 web rendering engine, containing many improvements for web developers, Add-on developers, and users. What’s new feature on this new version?
This first revision of the Beta of Firefox 3.6 / Gecko 1.9.2 introduces several new features:

• Users can now change their browser’s appearance with a single click, with built in support for Personas.
• Firefox 3.6 will alert users about out of date plugins to keep them safe.
• Open, native video can now be displayed full screen, and supports poster frames.
• Support for the WOFF font format.
• Improved JavaScript performance, overall browser responsiveness and startup time.
• Support for new CSS, DOM and HTML5 web technologies.

Firefox 3.6 beta is an early release, so only download if you’re comfortable running less than completely stable software. You can read officially announcement and download it via Mozilla Blog