Firefox 4 notches up 6m downloads in 24hUpdated Firefox browser outperforms IE9

23 March 2011

Firefox 4 web browser tab screenshot

Mozilla yesterday announced the official release of Firefox 4, the latest version of its web browser, which it described as 'the fastest Firefox yet... between two and six times faster than previous releases'.

Firefox 4 has been downloaded more than 6 million times in the first 24 hours following release. This is more than double the number of downloads reported for Internet Explorer 9 during the recent same post-launch period.

The final release of Firefox 4 comes after 17 alpha and beta releases lasting for more than a year, resulting in feedback from millions of testers. It's Mozilla's first major browser release since Firefox 3 was launched two years ago, and packs a variety of improvements.

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Firefox 4 user interface

Firefox 4 has a new user interface, which positions tabs at the top of the screen and removes the traditional top menu bar, giving more screen space for browsing. New features in Firefox 4 include app tabs which can pin always-open websites to the Tab Bar as icons for easy access.

There are also Tab Groups, which allow users to collect multiple tabs into groups, and switch between them - ideal for working on different tasks, or to differentiate between work and fun browsing.

The claimed speed improvements stem in part from a new JavaScript engine, and Mozilla's own figures suggest that in three major speed tests Firefox outperforms Firefox 3.6 by at least a factor of three. Firefox 4 also adds WebGL 3D graphics which should allow more complex gaming and visualisations to be added to websites. 

Firefox 4 also bills improved crash protection among its strengths. If Adobe Flash, Apple QuickTime or Microsoft Silverlight plugins crash or freeze, it shouldn't cause your whole Firefox window to crash. Instead, users should be able to reload the offending page to restart the plugin.

Users of Firefox 4 are also set to benefit from improved security and privacy controls.

Firefox 4 can sync across multiple devices, including smartphones, and not only synchronises bookmarks, but also browsing history, and even the tabs you currently have open.

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Download or upgrade to Firefox 4

Unlike the latest version of Microsoft's rival browser - Internet Explorer 9 - Firefox 4 works on Windows XP as well as Vista and Windows 7. Firefox 4 is also available for Mac OS X and Linux, with versions for mobile operating systems Android and Maemo in the pipeline.

Existing Firefox users can upgrade to the latest version by clicking on the 'Help' menu and choosing 'Check for updates'. Alternatively, the new browser is available as a free Firefox 4 download on

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