Today marks the release of Firefox 5, only three months after Firefox 4 has been released. Due to the lengthy development of Firefox 4 the development team shifted to a rapid release model. Firefox 4 development took about a year and many features that were already done couldn’t be delivered to users. Now more frequent releases with smaller updates will happen.

Firefox 5 indeed doesn’t come with a long list of changes, in comparison to Firefox 4. As evidenced by the Firefox 5 release notes (at the time of writing these were still marked beta), there have been some minor additions and a lot of improvements. The major new feature is support for CSS Animations. Basically it allows to animate content via CSS, including special control functions and definition of keyframes. The other changes include better canvas, memory and networking performance, improved support for HTML5 and other standards. Lastly, inactive tabs will only be processed once per second, thus improving overall performance and hopefully battery life.

Most notably, Firefox no longer supports cross-domain loading of WebGL textures. This was made in a bid to improve security. Recently, there have been some reports about how WebGL is bad for security, since shader code runs directly on the graphics hardware. This was fueled by a Microsoft blog, though other people at Microsoft advocate to use WebGL and deal with the issues.

Firefox 4 was a big success and managed to achieve 227.1 million downloads since the launch on March 23rd, as witnessed by Mozillas Glow website, which has been moved to their web archive. Until today, there have been about 1000 downloads per minute, give or take depending on time of day. In a blog post Mozilla developers note that they will probably offer a new iteration of that website to measure Firefox success with the new rapid release model in mind.

Worldwide Browser Statistics by StatCounter
Worldwide Browser Statistics by StatCounter

As evidenced by browser market share stats courtesy of StatCounter, Firefox couldn’t increase its market share within the last two years. In fact due to the aggressive development of Chrome, Firefox lost about 2.5% of marketshare over the course of one year. In the same timeframe, Internet Explorer lost about 9%, but Chrome gained about 11% of share. Thus the developers of Firefox decided to push releases and thus new features and improvements faster to their customers.

Apparently the developers already prepare for a big online release party. They have set up an IRC channel, which can also be joined on a JavaScript based website and will be spreading the word on Twitter. On top of that, they offer to join the celebrations via phone ? at least the US number is said to be toll free.

For now, the Firefox website doesn’t offer the new release yet. However, the final release of Firefox 5 has been available on Mozillas FTP server since Saturday. You can take your pick here for Windows, Mac OS and Linux.

The next release is already around the corner. Firefox 6 will enter the beta phase on July 5th and should be ready for release sometime in August. Daring users can download the Aurora release branch to check out the new features of the next release.