If you are running a recent distribution release, say, Ubuntu 11.04 or Linux Mint 11, you are likely running Firefox 4. But what if you want to run the bleeding edge version (of Firefox), that is the Daily Build?

Not long ago Mozilla changed the release cycle of Firefox, so that major new versions (Firefox 5, 6 and so on) will be released every 2-3 months. Currently, the latest alpha release is Firefox 6 Aurora, while the latest beta development version is Firefox Beta 5, which has made it into the Firefox Next PPA already. Installing this version should be very easy if you follow the next steps.

Mozilla today released Firefox 3.5 Release Candidate 2, which you can download from Mozilla's Web site. Release Candidate 2 is the first version of Firefox 3.5 that average users might want to run, since it's faster and more stable than the beta versions were. Firefox 3.5 boasts a number of significant changes.

Today, I ran an upgrade of my laptop, which runs Ubuntu. A nice little feature that came with this particular upgrade is a working installation of Firefox 3. About 2 months ago, I upgraded to Firefox 3, but it was in an unusable state, so back to Firefox 2.0 I went. With this working version though, I have to say that a downgrade back to Firefox 2 won’t happen again.

After changing its stable release policy to a more accelerated pace, Mozilla released Firefox 5 pretty quick after the latest major Firefox version was put out. Firefox 4 was released on March 22, 2011 and this version follows only three months later. Here’s an announcement on the Mozilla Blog website.

In this short guide I will show you how you can install the new Mozilla Firefox 4.0 browser (released March 22, 2011) on an Ubuntu 10.10 desktop. Fortunately, there's a Launchpad PPA repository that has Firefox 4.0 .deb packages, so we can easily install it through Ubuntu's package manager.

"[...]it's official: while Firefox 3 boasts some great new features like a smart address bar and better bookmarks manager, the best reason to upgrade will be for the performance improvements. Firefox 3 is noticeably faster and more stable than Firefox 2 to the casual user and Mozilla engineers have numbers that show it will be the fastest browser on the market."

Firefox, what's not to love about this open-source web browser? Well, a number of users following the development work on Ubuntu 8.10 (the Intrepid Ibex) are feeling rather outraged over Mozilla Firefox 3.0.2 and later. In the latest Ubuntu packages, Firefox requires an EULA (End-User License Agreement) be accepted the first time you launch the browser.

This guide explains several methods on installing the latest Firefox in Ubuntu, including installing it from a PPA repository.

I. Install Firefox from the Firefox PPA repository
1. The CLI (command-line interface) way
This is probably the easiest method. Don't forget to read the Creating a new profile section below after installing Firefox.