Accelerated release cycle brings us Firefox 5 just three months after Firefox 4
The latest version of Firefox is available for Windows, Mac, Linux and Android, and has "over 1,000 improvements and performance enhancements".
Firefox 5 includes the Do Not Track privacy feature in all releases, including the Android version, which makes it the first browser to support the feature on multiple platforms. If you haven't heard, Do Not Track enables users to tell websites that they wish to opt out of behavioural tracking. At this stage, compliance with the request is down to the advertisers and websites. This feature is now more prominently displayed in the preferences.
The big new development is that the release for Windows, Mac and Linux now supports CSS animations. In response to the security concerns about WebGL, cross-domain textures have been disabled. This has broken some pages, but Mozilla is looking for a solution, which you can read about here: hacks.mozilla.org/2011/06/cross-domain-webgl-textures-disabled-in-firefox-5/. There's also improved standards support for HTML5, XHR, MathML, SMIL, and canvas, and various other stability, performance and security enhancements. The release notes are here www.mozilla.com/en-US/firefox/5.0/releasenotes/.
Mozilla announced in April that it is moving to a rapid release development cycle, much like Google Chrome's schedule.