Feb 3, 2011 15:24 GMT  ·  By

Mozilla has already made available for download two preview releases of the upcoming development milestone for Firefox 4.0. Early adopters can now grab and start testing 4.0b11-candidates, which are essentially pre-Beta 11 nightly builds of Firefox 4.0.

Users should be aware that there are just candidate releases of Firefox 4.0 Beta 11 and not the fully-fledged eleventh Beta of the upcoming major version of Mozilla’s open source browser.

In fact, the browser vendor doesn’t really expect to be shipping Firefox 4.0 Beta 11 until next week, so customers will need to exercise their patience a tad longer.

“As with previous betas, we're going to keep nightly builds pointing at the Beta 11 candidate for several days while QA runs through their testing. We won't have a ship date for Beta 11 until we've had some time to digest that feedback, but early next week is a good bet,” revealed Asa Dotzler, Director of Community Development, Mozilla.

The open source browser vendor had initially planned to make Firefox 4.0 Beta 11 the final Beta, but it appears that this won’t be the case.

In fact, Mozilla already confirmed that it is hard at work on a yet another development milestone ahead of the Release Candidate stage, Firefox 4.0 Beta 12.

“With a handful of betaN+ hardblockers still outstanding post Beta 11, we are now working on Beta 12. The schedule for beta 12 has not been determined yet, but the number of remaining beta blockers is small enough that it could be our final beta.

“We currently stand at 194 softblockers and 67 hardblockers. 30 of those hardblockers are marked betaN+ meaning that they must get beta coverage,” Dotzler added.

In the context in which Beta 11 will only be delivered in the week of February 7th, followed by Beta 12 for which a release deadline has yet to be set, and with at least one RC Build after that it’s pretty clear that Firefox 4.0 won’t be finalized by the end of this month.

Firefox 4.0 Beta 10 for Windows is available for download here.

Firefox 4.0 Beta 10 for Linux is available for download here.

Firefox 4.0 Beta 10 for Mac is available for download here.