Firefox 4 is based on the Gecko 2.0 Web platform and was released on March 22, 2011. This release features JavaScript execution speeds up to six times faster than the previous version, new capabilities for Web Developers and Add-on Developers such as hardware accelerated graphics and HTML5 technologies, and a completely revised user interface.
- Firefox 4 is available in over 80 languages
- Uses JägerMonkey, a new, faster JavaScript engine that is up to six times faster than Firefox 3.6
- Support for the Do Not Track (“DNT”) header that allows users to opt-out of behavioural advertising
- Firefox Sync is included by default, allowing you to securely synchronize between multiple computers and mobile devices
- Certain graphics rendering operations are now hardware-accelerated using Direct3D 9 on Windows XP, Direct3D 10 on Windows Vista and 7, and OpenGL on Mac OS (OpenGL on Linux will be supported in the future)
- Direct2D Hardware Acceleration is now on by default for Windows 7 users
- WebGL is enabled on all platforms that have a capable graphics card with updated drivers
- Native support for the HD HTML5 WebM video format, hardware accelerated where available
- Firefox button has a new look for Windows Vista and Windows 7 users
- Tabs are now on top by default on Windows, Mac OS X, and Linux
- You can search for and switch to already open tabs in the Smart Location Bar
- The stop and reload buttons have been merged into a single button on Windows, Mac OS X, and Linux
- The Bookmarks Toolbar has been replaced with a Bookmarks Button by default (you can switch it back if you’d like)
- Crash protection for Windows, Linux, and Mac OS X when there is a crash in the Adobe Flash, Apple Quicktime or Microsoft Silverlight plugins
- You can turn any tab into an “App Tab” by right-clicking on it and selecting “Make into App Tab” from the context menu
- The default homepage design has been refreshed
- Overhaul of the bookmarks and history code, enabling faster bookmarking and startup performance
- Per-compartment garbage collection is now enabled, reducing work done during complex animations
See the complete Firefox 4.0 Release Notes for full details.
