For the full list of changes since the alpha release, see this list (it’s big).

Web developers and Add-on developers should read more detail about the many new features in Firefox 3.6 for developers on the Mozilla Developer Center.

Support for new CSS, DOM and HTML5 web technologies.

Improved JavaScript performance, overall browser responsiveness and startup time.Open, native video can now be displayed full screen, and supports poster frames.Firefox 3.6 will alert users about out of date plugins to keep them safe.Users can now change their browser’s appearance with a single click, with built in support for Personas.A mechanism to prevent incompatible software from crashing Firefox.(New in this update) The ability to run scripts asynchronously to speed up page load times.(New in this update) A change to how third-party software integrates with Firefox to increase stability.The Beta of Firefox 3.6 / Gecko 1.9.2 introduces several new features for users to evaluate: Your beta software will update itself periodically, and eventually will be updated to the final release itself. The Mozilla community appreciates your feedback and assistance in testing this preview of the next version of Firefox.

If your favorite Add-on isn’t yet compatible, you can also download and install the Add-on Compatibility Reporter – your favorite Add-on author will appreciate it! More than half of the thousands of Firefox Add-ons have now been upgraded by their authors to be compatible with Firefox 3.6 Beta. This update contains over 80 fixes from the last Firefox 3.6 beta, containing many improvements for web developers, Add-on developers, and users. Last night the Mozilla community released Firefox 3.6 Beta 3, making it available for free download and issuing an update for all Firefox 3.6 beta users. Check out the Mozilla Developer News announcement reposted below for more details. Editor’s note: Mozilla released Firefox 3.6 beta 3 on Tuesday, November 17, 2009.

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