Mozilla will probably add a third beta to the development schedule for Firefox 3.1 to get a better handle on remaining bugs and give several new features, including a faster JavaScript engine and a private browsing mode, more testing time, the company's browser director said Tuesday.
Previous schedules published by Mozilla had limited Firefox 3.1 to only two betas before moving to a release candidate.
In a long post to the "mozilla.dev.planning" forum, Mike Beltzner, the director of Firefox, said that Beta 3 is necessary to get a feel for the severity of the remaining bugs and an idea of how long it will take developers to eradicate them. In addition, another beta will give more exposure to features landing in the browser only as of Beta 2, which has not yet been released.
Beltzner named several of Firefox 3.1's high-profile additions, including the new "TraceMonkey" JavaScript rendering engine and the so-called "porn mode" feature, dubbed "Private Browsing Mode" by Mozilla, among those that would benefit from more testing.
Beta 3 is not a done deal, Beltzner noted in a follow-up e-mail to Computerworld Tuesday, but he is confident that developers would approve the plan. "We're never comfortable declaring new milestones by fiat, but I expect that there won't be any opposition to the plans for a third beta at today's meeting," he said. "I'd say that it's very likely at this point."
So far, Mozilla has shipped only Beta 1, which was released six weeks ago, although Beta 2 should be available in early December, perhaps as soon as the end of next week. A schedule for the third beta has not been set, but Beltzner said Mozilla would likely declare a "code freeze" -- a milestone after which changes are either forbidden outright or tightly restricted -- in early January.
In his e-mail Tuesday, Beltzner stressed that the extra beta wouldn't delay the final version of Firefox 3.1. "We believe we can do this without major impact to our shipping schedule," he said. "It's more a matter of inserting another public consultation milestone than it is about slipping, per se."
Mozilla is traditionally leery of committing to final ship dates -- like other developers it typically says it launches products when they're ready, not on a timetable -- but previously it had said it was shooting for a late 2008 or early 2009 window. Tuesday, however, Beltzner said that Firefox 3.1 is "still looking at late in Q1 2009 for final delivery."