I know a few guys who are still running a Firefox 3.6 version and they will be glad to hear that the update prompt is opt-in. Users can decline and stay on their Firefox 3.6 version, at least for now (Mozilla says decline and I’m not sure how this goes along with the update being opt-in, but we will see).

Mozilla expects to move regular Firefox users to the new version. Christian Legnitto notes that the update’s main intention is to make users aware of the new version of Firefox to give them an option to update their web browser to the new version.

Based on previous advertised update offers we expect to see a significant percentage of users installing the new version. We are, of course, watching the data closely to see what happens and to make sure there are no unexpected issues.

Considering that Mozilla already prompted Firefox 3.6 users to update when Firefox 4 and Firefox 5 were released, I’d say it is questionable if many will take the opportunity this time to move to the newest version of the web browser.

The time of Firefox 3.6 is regardless of that slowly coming to an end. With the new suggested Extended Support Releases of Firefox comes the end of support for the Firefox 3.6 branch. It is not clear yet if Mozilla will make Firefox 8 or Firefox 9 the first ESR release but when that happens it is game over for Firefox 3.6.

Are you still running Firefox 3.6? If so, what is your main motivation to stay with the browser and avoid the new Firefox updates?

Update: Mozilla has postponed the advertised update notification. According to Christian Legnitto the update has been postponed to make sure the “server capacity is sufficient for release”. No word yet on the new date for the update.

The majority of Firefox users is subscribed to the stable channel. The latest official version of that channel is Firefox 5.0.1 which will be updated to Firefox 6 on Tuesday.

But Firefox Stable is not the only channel that has received an update that is already available on the Mozilla ftp server. The Firefox 3.6.x branch is still actively maintained, and users of that branch will be quite happy that their version of the Internet browser receives an update as well. Firefox 3.6.20 is also available on the ftp server.

Firefox users who do not want to wait that long can download the new version of Firefox can download the new versions from one of the official mirror servers like this one.

Cautious users should wait until the release is officially announced on the Mozilla site and via the automatic update option of the web browser itself. It is unlikely that we will see last minute changes but it has happened in the past.

So what is new in Firefox 6? The official release log has not been updated yet. The beta changelog lists the following changes:

The address bar now highlights the domain of the website you’re visiting
Streamlined the look of the site identity block
Added support for the latest draft version of WebSockets with a prefixed API
Added support for EventSource / server-sent events
Added support for window.matchMedia
Added Scratchpad, an interactive JavaScript prototyping environment
Added a new Web Developer menu item and moved development-related items into it
Improved usability of the Web Console
Improved the discoverability of Firefox Sync
Reduced browser startup time when using Panorama

The full list of changes of Firefox 6 is available here.

Only the beta release notes are available for Firefox 3.6.20 as well. The list is considerably shorter: The developers have fixed security and stability issues, and enabled downloadable font support for users running Mac OS X 10.7.

Big changes and features that will make an impact are already implemented and tested in Firefox 7. This is the version of the browser that will reduce memory usage significantly on many systems. (see Firefox 7 Aurora Shows Significant Memory Usage Improvements). (via)