Microsoft may have told app developers "Don’t call it Metro," but the latest version of Mozilla's browser for Windows 8 is called the "Firefox Metro Preview." The name is fitting in all senses.

It’s fitting because Mozilla has adopted the used-to-be-called-Metro design style with an attractive overhaul of the browser’s user interface. This is something Google did not do with Chrome. While there is a version of Chrome for Metro, it looks almost exactly like the desktop version, for better or worse.

The name "Firefox Metro Preview" is also fitting because "preview," if anything, is a polite word for this early state of the application. While both Microsoft and Google have Metro-style browsers in functional shape, Mozilla’s current schedule will keep the Metro version of its browser in beta for some time after the Windows 8 release on Oct. 26.

I installed the Firefox Metro Preview for Windows 8 RTM today on a Samsung Series 7 tablet with a 1.6GHz Intel Core i5 processor, 4GB of RAM, and an SSD drive. It’s probably too early to run benchmarks on the browser—but I did it anyway. Firefox actually beat IE10 in the Google Octane JavaScript benchmark, but lost in SunSpider, and simply could not complete the Peacekeeper HTML5 test.

The benchmarks show some promise, and the browser's existing features work pretty well. Everything it can do, it does quickly and smoothly. But there are lots of missing pieces, as noted by Firefox developer Brian Bondy in his blog. There is no panning and zooming. Scrolling is possible with touch, and a keyboard, but not with a mouse scroll wheel.

Flash and add-ons are both disabled for now. "Although we have plans for Flash support, the preview currently has it disabled," Bondy wrote. "You can add support for windowless plugins by setting plugin.disable to false in about:config. As previously mentioned, for the Metro environment only, even in the initial release, we will not have add-ons enabled. We will eventually add support for add-ons through the add-on SDK."

I experienced an odd bug myself that seems to be localized to my home office in Massachusetts. I cannot copy text in Firefox and paste it into a second application. I can copy and paste from another application into Firefox, but not vice versa. I tried both on the tablet and in a virtual machine, and even tried reinstalling Firefox, but am still having the problem.

My colleagues Andrew Cunningham and Sean Gallagher both tested it out and found copying and pasting does work on their machines. I won’t rule out operator error—whatever is causing my own problem, I am sure the answer lies somewhere deep within the Windows Event Viewer.

Metro Metro Metro

The Firefox Metro Preview is in the latest nightly build of Firefox version 18 (download link), which is scheduled for release Jan. 8, 2013 (the current stable version is 15). You can install both Firefox 15 and 18 side-by-side on Windows 8—Firefox 18 will simply be called "Nightly." The difference is that Firefox 18 includes both the desktop and Metro versions, while 15 includes only the desktop one. If you set Nightly as the default browser, and then access it from the Start Screen, it’ll load the Metro version. (Clarification: The build that includes Firefox Metro Preview is in a branch from Mozilla's normal nightly builds. The build with Firefox Metro will be merged with the main development version sometime in the next three months.)

When you open Firefox Metro, you'll see bookmarks on the left, recent pages in the middle, and downloads on the right. There is a single box at the top to type in a Web search or a URL, unlike the desktop version of Firefox which has separate boxes.

Interface-wise, it’s much more similar to IE10’s Metro version than Chrome’s. That means buttons and menus are optimized for touch, with bigger surface areas to accommodate the use of fingers instead of a mouse. But there are fewer options. There seems to be no way to have an always-present bookmarks bar like there is in Chrome, for example.

Webpages are displayed full-screen by default. If you swipe in from the top (or right-click at the top with a mouse) you reveal the URL/search bar and a plus sign for opening a new tab. If you swipe from the top or right-click a second time, the view expands to include open tabs:

There is an option to always show all tabs, instead of having to swipe down to show them. There are also obvious ways to bookmark pages or pin them to your Start Screen. The best way to easily access your bookmarks is to start a new tab page, which by default lists your bookmarks, recent pages, and downloads. There is not yet an option for creating new bookmark folders.

One handy feature lets you share the URL of whatever webpage you’re viewing by swiping in from the right to bring up the Windows 8 share contract. That lets you e-mail the URL or share the link via Facebook, Twitter, or LinkedIn, all without leaving Firefox.

Mozilla's sync service for syncing bookmarks and other data across devices is also enabled. But I haven't been able to download synced bookmarks, even though Firefox Metro claims it's completed the sync operation.

Benchmarks

On to the benchmarks! I attempted four tests, the three mentioned above (SunSpider, Google Octane, and Peacekeeper), and a Microsoft HTML5 test known as Chalkboard. All were performed on the Samsung Windows 8 tablet.

Chalkboard seems to be a test that only IE can perform well. While IE10 completed the test in 8.26 seconds, it took Firefox Metro 757.88 seconds (12.63 minutes), and Chrome simply couldn’t finish it at all.

Even if we discount this test, IE10 feels fast in Windows 8 and it outperformed the competition in SunSpider. While IE10 completed the SunSpider JavaScript benchmark in 302.8ms, Chrome took 413.6ms and the Nightly Firefox took 459.2ms.

Firefox Metro’s best result came in Google Octane, where it scored 4,928, much better than IE10’s 1,465. Chrome hit 7,056. The results were so disparate that I ran the tests again, and got nearly identical results.

With PeaceKeeper, Firefox Metro wasn’t able to finish the test at all, on either the tablet or in a VM. Chrome (on the tablet) scored 1,998, better than IE10’s score of 1,071.

The results just stated include the Nightly build of Firefox 18. Since we were comparing the browser to stable versions of Chrome and IE10, it’s only fair to run the same tests on Firefox 15 as well.

The results were better and worse. Firefox 15 on the Windows 8 tablet did SunSpider in 345.4ms, scored 4,653 on Google Octane, and did the Microsoft ChalkBoard test in 279.78 seconds. Firefox 15 was able to finish PeaceKeeper, coming up with a score of 1,307.

A late start. Does it matter?

Firefox obviously got a slow start in having a Metro-ready browser for the Oct. 26 launch of Windows 8. Internet Explorer 10 is ready, of course. Chrome is too, in a sense, because Google didn't change the user interface much, perhaps betting that most Windows 8 users will be using traditional mice-and-keyboard setups instead of tablets. Mozilla has a long road ahead, as evidenced by the state of this first version and its target date of January for a Firefox 18 release.

Firefox product manager Asa Dotzler writes in his blog that "Over the coming weeks and months, we’ll be adding more features, tightening up Windows integration, improving performance and responsiveness, and finishing up all the necessary work to deliver a first class Firefox experience for Windows 8."

The different states of Firefox and Chrome on Metro could indicate that the makers of the two browsers have very different strategies for Windows 8, or just that they are on extremely different development cycles. I downloaded the latest development build of Chrome and found its Metro interface to still be largely unchanged from its desktop version.

Firefox Metro, for all its early problems, is thus a lot closer to being a touch-ready browser on Windows 8 than Chrome. At the same time, the Metro version of Chrome is more stable than the Metro version of Firefox, precisely because it's generally the same as the desktop version. Google may have the more attractive browser than Firefox for Windows 8 users who use Metro with a mouse and keyboard. But for those who buy Windows 8 tablets, Firefox looks like it will be the better option once all its various bugs are fixed and its missing features restored.