New features and changes in this milestone that require feedback include:
* A new Private Browsing Mode that allows you to browse without Firefox storing any traces of where you've been - perfect for online holiday shopping!
* New functions that make it easy to remove the history of your past few hours of browsing, or remove all traces of a website.
* New support for web worker threads.
* Improvements to the Gecko layout engine, including speculative parsing for faster content rendering.
* Removed the new tab-switching & preview behavior based on feedback from Beta 1 users
* This beta is now available in 54 languages - get your local version and let us know if it looks right.