Previously, Dotzler said that he didn't believe a Firefox app for Windows 8 would be further along than a "late-stage Beta" this year.
Microsoft will launch Windows 8 on Oct. 25 during a several-hour event, and start selling the upgrade the next day. Also on Oct. 26, PC makers will begin selling systems pre-loaded with Windows 8.
Windows RT, the touch-only spin-off of Windows 8 designed for tablets, is an entirely different story, however, and complicates Mozilla's work. Unlike Windows 8, Windows RT bars all third-party developers from accessing the limited "desktop" mode; only Microsoft's programmers can call the APIs there, which they do to power much of the Modern version of IE10 on the tablet OS.
Mozilla howled, and in May accused Microsoft of anticompetitive behavior by purposefully blocking others from building browsers that could effectively compete with IE10.
So although Firefox for the Modern UI may work on Windows RT -- Microsoft has promised that apps written for that mode on Windows 8 will also run on the Modern-only Windows RT -- it will likely require not only considerable recoding, but will, Mozilla has said, be significantly slower than IE10 in rendering JavaScript.
In June, Google launched a preliminary version of Chrome for the Windows 8 Modern environment, but that app is less a reworking of its sibling than a minimalist effort that discards Microsoft's design guidelines.
Google has not set a launch date for its Modern-style browser, but looks likely to debut it alongside Chrome 23, which would ship sometime next month.
The Modern-enabled preview of Firefox 18 can be downloaded from a Mozilla server ( FTP download), but caveats abound: Users must be running Windows 8 RTM, and must set the browser as the operating system's default by following several steps outlined by Bondy in his blog.
The next non-Modern edition of Firefox, version 16, will launch Tuesday, Oct. 9.
Gregg Keizer covers Microsoft, security issues, Apple, Web browsers and general technology breaking news for Computerworld. Follow Gregg on Twitter at @gkeizer, on Google+ or subscribe to Gregg's RSS feed. His email address is gkeizer@computerworld.com.
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