Mozilla ships Firefox 3.6 release candidate, nears final

Computerworld - Mozilla on Friday shipped a release candidate build of Firefox 3.6 that, barring problems, will become the final, finished version of the upgrade.

Firefox 3.6 Release Candidate 1 (RC1), which followed a run of betas that started in early November, features nearly 100 bug fixes from the fifth beta that Mozilla issued Dec. 17. The fixes resolved numerous crash bugs, including one that brought down the browser when it was steered to Yahoo's front page.

Another fix removed a small amount of code owned by Microsoft from Firefox. The code was pointed out by a Mozilla contributor, and after digging, another developer found the original Microsoft license agreement.

"Amusingly enough, it's actually really permissive. Really the only part that's problematic is the agreement to 'include the copyright notice ... on your product label and as a part of the sign-on message for your software product,'" wrote Kyle Huey on Bugzilla, Mozilla's bug- and change-tracking database. Even so, others working the bug said the code needed to be replaced with Mozilla's own.

RC1 may be the last preview before Mozilla declares the edition done. "Should everything run smoothly during testing this is what will be released to our users as the official version after a beta period," noted a page on the Mozilla wiki dedicated to Firefox 3.6 RC1 testing.

If past practice is any clue, the final of Firefox 3.6 could be ready for downloading as early as Jan. 18. Last summer, Mozilla delivered the release candidate of Firefox 3.5 on June 20, then launched the browser 10 days later. In 2008, the window between the last release candidate of Firefox 3.0 and the final was 13 days.

RC1 was once slated for release in October 2009, with a final Firefox 3.6 scheduled for the following month. But Mozilla delayed Firefox 3.6 as it struggled to make deadlines, then decided Dec. 17 to issue a fifth beta rather than push for a release candidate. Even so, Mozilla maintained that it would get RC1 out by the end of 2009.

Mozilla has had trouble making its development schedules. In 2008, the company originally shot for a late-2008 release of Firefox 3.5, but eventually postponed the ship date to mid-2009 in order to add features and quash troublesome bugs in the then-new TraceMonkey JavaScript engine.

Among the new features in Firefox 3.6 are built-in support for the scaled-down browser skins dubbed "Personas;" warnings of out-of-date plug-ins; support for new CSS, DOM and HTML 5 technologies; support for full-screen video embedded with the video HTML tag; and support for the Web Open Font Format (WOFF).

TraceMonkey has also been refreshed to boost JavaScript performance, something Mike Shaver, Mozilla's chief engineer, bragged about last week on Twitter. "I am excited about upcoming JS [JavaScript] engine work, and I don't care who knows it," Shaver tweeted.

As is usual for a Firefox preview, not all of the available browser's add-ons are compatible with the release candidate. According to Mozilla, about 75% can be used with Firefox 3.6.

Firefox controls about 25% of the global browser market, according to the most recent data from U.S.-based metrics company Net Applications. But while Firefox's usage share remained flat last month, Google's Chrome surged into third place, pushing Apple's Safari into the No. 4 slot for the first time.

Firefox 3.6 RC1 can be downloaded from Mozilla's Web site for Windows, Mac and Linux. Users running a beta of Firefox 3.6 should see upgrade notices shortly if they haven't already.

Gregg Keizer covers Microsoft, security issues, Apple, Web browsers and general technology breaking news for Computerworld. Follow Gregg on Twitter at @gkeizer, send e-mail to gkeizer@ix.netcom.com or subscribe to Gregg's RSS feed .

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