Firefox 4, the next major iteration of Mozilla's open-source Web browser, is expected to be released toward the end of the year. Mozilla's director of Firefox, Mike Beltzner, is promising new beta versions every two or three weeks.
After years as the innovation leader in Web browser technology, Mozilla last year found itself unprepared to match Google's aggressive development of Chrome, not to mention the revitalized browser development at Apple and Microsoft. Firefox 4 represents Mozilla's effort to recapture mindshare and continue growing market share even as browser makers have shifted their focus from desktop to mobile distribution.
Firefox 4 Beta 1 looks different -- more so on Windows versions than Mac and Linux versions, which will get their facelifts later. Like Google Chrome, window tabs now sit atop the address bar.
Firefox user experience designer Alex Faaborg said in a blog post last month that the change is not about following Chrome. "The change to placing tabs on top isn’t about one browser versus another browser, it’s about the evolution of the Web as a platform," he said.
Indeed, in a video posted on his blog, he elaborates on the reasons for moving tabs to the top of the Web browser window: Doing so makes the user experience more intuitive and better accommodates future browser development. New capabilities in HTML5, like native Web app menus and toolbars, and forthcoming Firefox 4 features, like its panel-based notification system, are less confusing from a user interface perspective when tabs are on top.
Firefox 4 Beta 1 also introduces a new Add-Ons Manager to promote easier browser customization, support for hardware-accelerated HD-quality HTML5 video under the new WebM format championed by Google, plug-in crash protection, and faster start-up and page loading.
Internally, Firefox 4 Beta 1 features a revised HTML5 parser, a portion of Mozilla's Gecko layout engine that had gone without upgrades for years, support for real-time online data transfers through WebSockets, support for structured storage through IndexedDB, a Web Console for developers, and support for simpler Add-On development through a project called Jetpack.
But some important features are missing. Mozilla is still working on its process separation project called Electrolysis.
Perhaps even more significantly, Firefox 4 Beta 1 is slow, at least in terms of JavaScipt performance. Using the JavaScript Benchmark test on Celtickane.com: Apple Safari 5.0 (6533.16) (Mac) scored 617, faster than 98% of computers running the test; Google Chrome 5.0.375.99 (Mac) scored 599, faster than 97.4% of computers running the test; and Firefox 4 Beta 1 (Mac) scored 236, faster than 60.2% of computers running the test.
Web Worker Daily, using Mozilla's own Dromeo speed test, puts Chrome in the lead, followed by Safari 5, Opera 10.6, and then Firefox 4 Beta 1.
This is to be expected for unfinished software. But the final version of Firefox 4 has to get faster to remain competitive. Mozilla is looking for user feedback and is encouraging users to test drive the new software.