Mozilla has started offering Firefox 3.5 to users still running older versions of the browser, the first of what will likely be several attempts to get people to upgrade before support expires for Firefox 3.0.
Firefox 3.5.2, the current version of the edition launched last June, is now being offered to users running 3.0.13, the most up-to-date edition of Mozilla's 2008 browser.
Although users have been able to upgrade to Firefox 3.5 for two months by downloading the new browser or manually triggering 'Check for Updates' under the Help menu, this is the first automated update.
When Firefox users get the update offer, they can choose between accepting the update, postponing it 24 hours or declining it. The latter, however, doesn't permanently block future offers. "We might send you another offer again in the future, but it won't be for several weeks or months," explained Mozilla on its developer center.
Last year, Mozilla launched what it calls a 'Major Update' offer several times.
Not all users of Firefox 3.0.13 will see the upgrade offer at the same time; Mozilla rolls out such offers slowly at first to make sure its download network can take the traffic.
Firefox 3.0 users have until January 2010 to switch to the newer Firefox 3.5. At that time, Mozilla will halt production of security patches for the older version.