Mozilla Corporation has pushed back the release of the third, and possibly final, beta for Firefox 3.1 by a week to February 2. The setback won't affect the final release date for Firefox 3.1, according to the company, but was necessary to address a large number of remaining bugs – referred to as “blockers.”

Among the unfixed bugs are ones related to Firefox 3.1's new privacy mode, dubbed “Private Browsing,” a feature that debuted in Beta 2 last December, and several connected with the new ability to drag tabs from the browsing window.

In related news, Mozilla also announced a subtle but significant change to the way tabs work in Firefox, tweaking them so that when a new tab is opened from a link it will appear immediately to the right of the one you are working on. Referring to the change, Mike Beltzner, director of Firefox at Mozilla, says that this feature is one of the little things that don’t get a lot of attention when people talk about Google Chrome.