Mozilla slates overdue Firefox 3.1 beta for March 10

After several delays, Mozilla is set a release schedule for Firefox 3.1 Beta 3, the next milestone on the road to the browser's first major upgrade since June 2008.

According to notes posted on the Mozilla site following a weekly progress meeting, Beta 3 will be released next Tuesday at 5 p.m. EST. Those same notes specified a “code freeze” today at 8 p.m. EST, indicating that developers will accept no more changes in preparation for pre-delivery testing.

Last week, Mike Shaver, Mozilla's head of engineering, announced that work on Beta 3 would come to a close this week, regardless of whether a fix for a longstanding multi-issue bug in the browser's new JavaScript engine was ready. His decision followed comments by some Mozilla developers that the company had waited long enough for the patch, should proceed with the beta, and if necessary, slot another into the schedule.

The bug under the spotlight, which is in TraceMonkey, Mozilla's new JavaScript rendering engine, had not been completely resolved by late Monday.

To accommodate that fix, as well as other patches and possibly one or more new features, Mozilla has decided to insert a fourth beta into Firefox 3.1's development cycle. Previously, Shaver said it would arrive four to six weeks after Beta 3's release, which would put in the follow-up beta in April 7-21 time frame.

Mozilla conceived Firefox 3.1 as a “fast-track” upgrade that it originally intended to launch in late 2008. But the browser's progress has been slower than planned, and the company has reworked its schedule several times. Last November, for example, it added Beta 3 to the timetable to give developers more time to fix bugs and test features such as TraceMonkey.

This year, Mozilla first pushed back Beta 3's release in mid-January, then a week later again delayed delivery. In the interim, Mozilla had declined to set a public timetable, citing difficulties in estimating how long it would take programmers to fix several bugs.

Browser competition has been fierce of late, and the delays mean that Firefox 3.1 could be beaten to market by Microsoft Corp.'s Internet Explorer 8 (IE8), which reportedly will be finished later this month. And just last week, Apple Inc. unveiled a public beta of Safari 4, which ran through one JavaScript benchmark suite 38% faster than the most recent build of Firefox 3.1.

In related news, Mozilla plans to release Firefox 3.0.7 as a security update sometime Wednesday.