Firefox 3.5 is based on the Gecko 1.9.1 rendering platform, which has been under development for the past year. Firefox 3.5 offers many changes over the previous version, supporting new web technologies, improving performance and ease of use. Some of the notable features are:
Available in more than 70 languages.
Support for the HTML5
Improved tools for controlling your private data, including a Private Browsing Mode.
The ability to share your location with websites using Location Aware Browsing.
Support for native JSON, and web worker threads.
Improvements to the Gecko layout engine, including speculative parsing for faster content rendering.