It appears that Firefox won’t evolve directly from version 4.0 to 5.0, but that it will take a slight 4.x detour.
Christian Legnitto, Firefox release manager revealed that there “will be at least one Firefox 4.x release,” following the general availability of version 4.0 next week
Mozilla has already decided on March 22nd, 2011 for the launch of Firefox 4.0 Final which, for all purposes intended will be identical to the Release Candidate 1 (RC1) development milestone.
“Please note that this plan does not have any bearing on the proposed Firefox 5+ development plan as Firefox 4 was developed under a different system and has different needs,” Legnitto explained
“To reduce version confusion and be explicitly clear the updates will be referred to by codenames. There will be no debate about choices like 4.1 vs 4.0.1 or confusion about the content or schedules. Additionally, the update order maps to codename alphabetical order so you can easily see which comes first just by looking at the codename.”
Mozilla is working to transition to a faster pace release cycle which will mean that an increased volume of major Firefox versions will be delivered more frequently.
In this regard, the open source browser maker revealed that it expects Firefox 5.0, Firefox 6.0 and Firefox 7.0 to all be delivered by the end of 2011.
In fact, according to a draft for the release process, version 5.0 could follow 4.0 at approximately 16 weeks, with additional Firefox releases being offered to users some six weeks apart after that.
Legnitto already discussed two possible updates to Firefox 4.0, namely:
“Anteater - An optional update we will do if late-breaking issues arrive with the Firefox 4 launch and an update needs to be turned around in less than two weeks. This update may not be needed, but we don't want to be caught flat-footed if it is.
[And] Macaw - Regularly scheduled update slated to come out 2-3 weeks after Firefox 4 (or Anteater if it is indeed needed).”Firefox 4.0 Release Candidate (RC1) for Windows is available for download here.
Firefox 4.0 Release Candidate (RC1) for Linux is available for download here.
Firefox 4.0 Release Candidate (RC1) for Mac is available for download here.
Firefox 3.6.15 and Firefox 3.5.17 for Windows are available for download here.