Firefox 3.5 Pushes Mozilla Back Among the Top of the Browser Heap

By Jim Rapoza  |  Posted 2009-07-01

Firefox 3.5 Pushes Mozilla Back Among the Top of the Browser Heap

By pretty much any measure, Mozilla's Firefox browser has been a huge success. Firefox is one of the most successful open-source applications of all time, second only to the Apache Web server. And in just a few short years, Firefox has been able to take significant market share away from Microsoft's Internet Explorer, a task that seemed impossible when Firefox first launched.

But in the last year, Firefox has faced challengers in areas in which it was always comfortably ahead of IE, such as innovative new features, standards support and reliability. In many ways, the only claim to superiority that Firefox most recently had over rivals such as Apple Safari, Google Chrome and Opera was in its large community of add-ons.

However, with the release of Firefox 3.5, Mozilla has addressed many of the biggest problems of its Web browser. And, while most of the new features are under the hood, Firefox 3.5's improvements are enough to push it back among the top Web browsers in all areas and to make it one of the more significant new browser releases. The improvements are also enough to gain Firefox 3.5 an eWEEK Labs Analyst's Choice.

For images of Firefox 3.5 in action, click here. 

Among the biggest criticisms leveled at recent versions of Firefox have been slow performance and poor reliability, with many claiming that Firefox drags after long browsing sessions and that it is prone to crashing. To be fair, these problems were often due more to the add-ons used than to the browser itself, but, with Version 3.5, Firefox appears to have fixed most of these issues.

In my tests of the betas, release candidates and final version of Firefox 3.5, I have found the browser to be very stable. I've seen no noticeable slowdowns, even with large numbers of open windows and tabs.

And when it comes to performance, Firefox and its new browser engine look to have improved significantly. In multiple tests using online resources, including Futuremark's Peacekeeper benchmark, Firefox 3.5 showed considerable performance gains, more than doubling the speed of Firefox 3.0. And while it still lags behind performance leaders such as Safari 4 and Chrome 2.0, Firefox 3.5 is now much more comparable.

HTML 5 Support


HTML 5 Support

However, a much more significant new feature in Firefox 3.5 is its extensive support for HTML 5. Although it is not yet a full World Wide Web Consortium standard, HTML 5 is already offering an intriguing glimpse into the future of the Web. Indeed, HTML 5 is much more than just the next version of HTML; it is a reimagining of the Web and how browsers work, providing many of the same powerful GUI interactions that one gets from RIA (rich Internet application) platforms or even desktop applications.

One of the more interesting aspects of Firefox 3.5's support for HTML 5 is in its handling of video. Throughout the history of the Web, browsers have treated video as a second-class citizen, relying on plug-ins and other applications to handle video. However, through its implementation of HTML 5, Firefox 3.5 can handle video directly, in the same way that the browser can display images or text.

This means much more than just the ability to play video in a Web page. With this implementation, video can be integrated with other Web content in ways that are much more difficult to do using traditional methods. Video can react immediately to actions performed within the Web page, and Web content can be changed in response to things that happen within the videos. There are many interesting demos available on the Web showing the power of this integration, and I think they are just scratching the surface of what HTML 5 will enable.

While this is one of the most intriguing new capabilities of Firefox 3.5, it is not an edge the browser will hold for long.

Safari and Opera have also taken strides to support HTML 5, and other browsers will also soon follow. Of course, in the end, anything that increases the power of the Web and browsers is probably a good thing for Mozilla.

Along with the HTML 5 support, Firefox 3.5 has also boosted standards support in general. In the Web Standards Project's Acid3 test, Firefox 3.5 shows considerable improvement over previous versions and does well, though it is still behind Chrome, Opera and Safari (though well ahead of IE 8).

Playing Catch-up


Playing Catch-up

Most of the other new features in Firefox 3.5 are simply the browser catching up to capabilities that are already found in competing browsers.

From a visual standpoint, one of the only new things that users will notice in the new version is the inclusion of a new tab button in the tabs bar. Tab management has seen some minor improvements, though Firefox still lacks new tab features akin to Safari's Top Sites or Opera's Speed Dial (though it is possible to add similar capabilities through extensions).

With Version 3.5, Firefox joins most other modern browsers with the ability to run in a private browsing mode (often euphemistically knows as "porn mode"). When in this mode, the browser does not save data from the browsing session.

The privacy mode in Firefox 3.5 is fairly well-implemented. While other browsers use some form of icon to show that the browser is in privacy mode, Firefox simply displays the words "Private Browsing" within the browser's top title bar.

Private Browsing is launched either from the Tools menu or by hitting Ctrl-Shift-P. Launching the mode immediately starts a fresh browsing session, and when you turn it off, you are immediately returned to whatever pages you were viewing before launching the privacy mode. This model works well, though it is a little jarring. I would have liked the option to launch a separate private browsing window and keep a regular window open, as well.

It is possible within Firefox 3.5 to do some fine-grain post-session editing of a browser session. For example, when in the browser history, users can choose a site they've visited and select "Forget about this site" to remove all traces of having ever visited the Web site.

Another new feature in Firefox 3.5 is Location Aware browsing, which utilizes the Geolocation API. With this capability, a user can choose to share (or not share) his or her location with a Website to gain information, such as businesses in a certain area. This works through a number of methods, including IP address, Wi-Fi nodes and GPS systems. This feature will be less accurate for a desktop-bound system and more accurate for a mobile device or laptop. (And, of course, a Website can always learn your IP address and gain some location information, no matter what the browser does.)

As is typical when new versions of Firefox are released, not all extensions will work upon upgrading. In my tests, only a third of my extensions worked immediately after upgrading, but I expect that most extensions will be updated to work with Firefox 3.5 in the near future.

Firefox 3.5 is available for most operating systems, including Linux, Mac OS X and Windows. To download Firefox 3.5, go to

Chief Technology Analyst Jim Rapoza can be reached at

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