- The ability to sync add-ons between Firefox browsers across computers to create a consistent browsing experience everywhere. Note: Users will need to create an account to take advantage of this feature.
- History, cookies, bookmark migration from Google Chrome.
- Various HTML5 adjustments, including video controls.
- Improvements to CSS and 3D development tools.
You can access the full list of changes, including the various bug and security fixes here. Visit Firefox.com to try it out.