Firefox 4: A Speedy, Modern, Multiplatform Browser

The latest version of Firefox matches Google's Chrome on many fronts but lacks its Group Policy-based management support.

Firefox 4, the first full point release of Mozilla's popular open-source Web browser in nearly three years, combines user-interface, performance and Web-standards support enhancements with new provisions for making user data both more and less accessible across the network.

On one hand, the browser ships with a newly integrated Firefox Sync feature, which enables users to synchronize bookmarks, preferences, browser state and passwords between Firefox and Firefox Mobile browser instances through a server either hosted by Mozilla or self-hosted. On the other side, Firefox 4 builds on the private browsing features included in previous releases with new "do not track" functions for users concerned with the trails they may be leaving as they traverse the Web.

As a speedy, modern, cross-platform Web browser, Firefox 4 is well worth evaluating for any organization, particularly those with a heterogeneous mix of client operating systems. On this multiplatform front, however, organizations should also keep an eye on Google's Chrome, which tends to match Firefox in features and performance, and offers Group Policy-based management support that Firefox 4 lacks.

For those already running earlier versions of Firefox, version 4 will be well worth the upgrade-provided that any add-ons on which users rely are compatible with the new version.

Firefox 4.0, which I tested in release candidate form, is available for free download at, and comes in versions for Windows, OS X and Linux.

Testing Firefox 4

Speed is one of the most important evaluation characteristics for any modern browser, particularly concerning Javascript, on which most Web applications depend. With Firefox 4, Mozilla debuts a new JavaScript engine, called J???gerMonkey, which in my tests delivered significant speed increases on JavaScript benchmarks. I tested the x86 versions of Firefox 3.6.15 and Firefox 4.0 RC1, downloaded straight from Mozilla's Website, on my Ubuntu Linux notebook.

On the SunSpider 0.9.1 JavaScript benchmark hosted at the project site for the WebKit rendering engine, Firefox 4.0 turned in an overall score that was more than four times faster than Firefox 3.6.15. On Google's V8 JavaScript benchmark suite, Firefox 4.0 turned in overall scores that were over eight times faster than version 3.6.15.

Anecdotally, the speed differences were certainly noticeable to me when browsing with the older and newer Firefox versions, bringing Mozilla's browser in line with what I've come to expect from Google's Chrome Web browser.

Firefox 4 has also come closer to Google's browser in its appearance. Many of the user-interface changes in the latest Firefox edition are aimed at reducing the amount of real estate the browser occupies, putting more emphasis on the Web content.

For instance, Firefox 4 does away with its "status" bar, which ran across the bottom of the application. The most useful job of the status bar was to provide a spot to show the Web address attached to hovered-over page links-which are crucial for spotting suspicious addresses before clicking through to them. In version 4, with the status bar gone, page links would simply appear in the former status bar area when I hovered over them.

Also, like Google's Chrome, the tab bar in Firefox 4 moves to the top of the interface, and the traditional menu bar (File, Edit, View, etc.) can collapse into a single "Firefox" button-a much thriftier use of space for these seldom-clicked menu items. I particularly appreciated these UI changes while testing Firefox 4 on a netbook machine, where vertical space is in short supply.

Tabbed browsing, while unremarkable these days, was one of Firefox's early differentiators, and the Mozilla team has continued refining this feature in Firefox 4. The first of these refinements to catch my eye was the "App Tab" feature, which allowed me to convert any browser tab to a narrowly sized tab, pinned to the far left of my tab bar, which would automatically open in future browser sessions.

I found that application tabs came in handy for frequently used Web applications, such as for Gmail or Twitter, where I would have the applications close at hand whenever I needed them. I would like to see Mozilla expand upon the application tab feature with process isolation for these pinned Web applications. I would feel safer running key Web applications in the same browser session as regular Web pages with this additional separation in place.

Elsewhere on the tab-management front in Firefox 4 is Panorama, a tab-grouping feature that was previously known by the code name "tab candy." Panorama is aimed at helping users deal with large numbers of tabs, which, as any Web user can attest, can quickly multiply out of control in a typical day's browsing.

I used Panorama to arrive at a zoomed-out view of my open tabs, and to drag related tabs into separate groups, which I could then dive back into individually. I used Panorama's search feature to locate particular tabs from the zoomed-out Panorama view.

In my own browsing, I've developed a discipline around keeping my open tabs to a manageable number, and turning to history to return to recently closed items, but Panorama may allow me to become less parsimonious in my tab use.

Also affecting my browser habits is the integration of Firefox Sync in version 4.0. Sync, which was previously available as an experimental feature under the handle Mozilla Weave, enables users to synchronize their browser settings, bookmarks and passwords in encrypted form to a central server. I tend to browse the Web from a handful of different machines, and the Sync feature made it much easier to switch between these systems. I tested with a sync server hosted by Mozilla. It's possible to host one's own server, as well, but the installation instructions for setting up a custom server are fairly rough around the edges at this point.