Mozilla released a second version of the Firefox 3.6 beta yesterday, and issued an update for the first Firefox 3.6 beta. The new build contains over 190 fixes from the original beta, along with several improvements for web developers, add-on developers, and users.

Among the fixes is a mechanism that prevents incompatible software from crashing Firefox. New features include built-in support for Personas, an alert for out of date plug-ins, the ability to display open, native video at full screen, support for poster frames, the WOFF font format, new CSS DOM and HTML5 web technologies, and improved JavaScript performance as well as overall browser responsiveness and startup time.

Mozilla notes that developers can read more about the new features in Firefox 3.6 on the Mozilla Developer Center. You can download the second Firefox 3.6 beta here: Windows, Mac OS X, Linux. Remember that many add-ons may not work with 3.6 yet, but you might have luck with this workaround.