If for some reason you were thinking of sticking with Firefox 4 and not upgrading to Firefox 5, well, don't. Mozilla has confirmed that Firefox 4 has reached its end of life and there will be no more security updates.
Mozilla released Firefox 4 only three months ago. After the release, there has been one update - Firefox 4.0.1 - meant to fix some secuty flaws. That is the last update the Firefox 4 will be getting. According to Daniel Veditz, Security Lead at Mozilla, Firefox 5 is the security update to Firefox 4.
Several people have repeatedly said in public places (newsgroups, planning meeting, Monday meeting; could not find a blog or wiki page) that Firefox 5 will be the security update to Firefox 4, and that there will be no 4.0.2 unless some issue between now and shipping Fx5 requires a chemspill response.
Related: Firefox 5 Benchmarked – Faster And Better Than Ever Before!
Along with the new versioning and release schedule, Mozilla is taking a leaf out of Google Chrome. With Google Chrome the installed application is updated regularly to the newer releases and the older releases are not supported. To do that, Chrome uses a background auto update mechanism. Firefox still does not have the auto update, but with the newer releases, updating to a newer version has been made much easier.
Mozilla's decison to not support the older releases makes a lot of sense if you consider the releases they are planning. They are not yet done with Firefox 5, they plan on releasing Firefox 6 and 7 as well this year. With such kind of release schedule, supporting all the older releases just doe not make sense.
via: Computer World
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