The latest version of Firefox has the following changes:

• Add-ons installed by third party programs are now disabled by default
  
• Added a one-time add-on selection dialog to manage previously installed add-ons
• Added Twitter to the search bar
• Added a preference to load tabs on demand, improving start-up time when windows are restored
• Improved tab animations when moving, reordering, or detaching tabs
• Improved performance and memory handling when using
• Added CORS support for cross-domain textures in WebGL
• Added support for HTML5 context menus
• Added support for insertAdjacentHTML
  
• Improved CSS hyphen support for many languages
• Improved WebSocket support
• Fixed several stability issues