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Mozilla releases Firefox 4 worldwide

The new-look browser features HTML 5 support, a redesigned user interface and added privacy features. Mozilla also said that tweaks to the JavaScript engine make it the fastest Firefox yet

Firefox 4 is now available for download, bringing with it anti-tracking privacy, HTML 5 compatibility and hardware acceleration.

Firefox logo

Firefox 4 has been released worldwide, promising anti-tracking technology, HTML 5 support and hardware acceleration. Photo credit: Mozilla

The fourth full-scale version of the Mozilla browser arrived on Tuesday, after missing both its initial release target of October and its revised target of February. As well as introducing new features, the update revamps existing components such as the TraceMonkey JavaScript engine.

As with other recent high-profile browser updates, the browser interface has been revamped with the aim of providing a better browsing experience. For example, open tabs are now placed above the search and address bars.

"With dramatic speed and performance advancements across the board, Firefox is between two and six times faster than previous releases. Major enhancements to the JavaScript engine make everything from start-up time to page-load speed to graphics and JavaScript performance screaming fast in Firefox," Mozilla said in a statement.

With dramatic speed and performance advancements across the board, Firefox is between two and six times faster than previous releases.

– Mozilla

The performance boost in Firefox 4 comes in part from its hardware acceleration features, seen as a staple for next-generation browsers — as is HTML 5 compatibility.

"Firefox brings the level of HTML 5 support up a few notches, [in what is] already one of the most standard-compliant browsers in the industry," Al Hilwa, program director in IDC's application development software research unit, told ZDNet UK.

One new security feature is a content policy that blocks cross-site scripting attacks on the browser by identifying legitimate content, Mozilla said.

Do Not Track option

The most publicised new feature is the Do Not Track privacy option that allows a user to specify whether they want their browsing data sent to third-party advertisers. However, unlike the tracking protection in Internet Explorer 9 (IE9), Firefox 4 does not use a 'blacklisting' approach.

Instead, it relies on header information that communicates the desire not to be tracked by advertising companies; these companies then need to honour that request and not collect data. However, the need to place trust in third parties to carry out the request could see Firefox 4 lose favour among business users and IT administrators, given that rival browsers leave the control with the user.

"I am happy that they are making an effort in the tracking protection, but really anything that does not put the protection in the hands of users is probably not going to be adequate," Hilwa said. "I think IE9's 'do not track' list technology is more likely to win privacy advocates and corporate users who concern themselves with the data moving outside of their firewalls due to the tracking activities."

However, the extensibility features and accompanying ecosystem in Firefox are key factors in its appeal to power users, according to Hilwa.

Windows XP support

In addition, unlike IE9, Firefox 4 will run on Windows XP — which is still being used by 67 percent of businesses in the UK — making it possible for widespread enterprise deployment.

"Of course [supporting XP] will help it in the battle with IE9, which is also a formidable offering but does not support Windows XP, and so is out of bounds for corporations that have not upgraded," Hilwa said.

Firefox has certainly upped its game with the new release and it is important for them to keep up with the fast-and-furious release schedule of Chrome.

– Al Hilwa, IDC

Mozilla's decision to switch to a Chrome-style version schedule in order to allow for more frequent and regular releases will also help Firefox compete with competitors such as Chrome and Internet Explorer, the analyst suggested.

"Firefox has certainly upped its game with the new release and it is important for them to keep up with the fast-and-furious release schedule of Chrome," Hilwa said. "Changes in the pace of application development for Firefox are welcome and should allow the technology to be evolved on a faster schedule."

Ahead of the full launch, Mozilla released the final build to its FTP download site where users began downloading it before the announcement. At the time of writing, the counter on the Firefox 4 download page was showing that the new build has been downloaded more than 384,000 times already.

Firefox 4 is available to download now, for free, for Windows, Mac or Linux systems.


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