Mozilla releases Firefox 4

By on March 21, 2011, 10:30 AM
Mozilla has released Firefox 4. The final build comes less than two weeks after Release Candidate 1. The company originally found no major problems in the RC1 build, and decided to release RC1 as the final version, but then changed its mind. An RC2 build was quietly pushed out on March 18, 2011 with a few fixes, and today the final bits appeared on Mozilla's servers.

If you're already running a previous build of Firefox 4 you should see an automatic update starting tomorrow. Alternatively, you can download the final build directly for Windows, Mac OS X, and Linux 32-bit/64-bit. The final version supports 83 languages.



Mozilla is letting users update Firefox versions 3.5 and 3.6 to 4.0 without the need to navigate to a download page. Firefox 4.0 was supposed to be released tomorrow, and while the download links are up, we expect that the official launch will be announced in the next 24 hours. For more information on what's changed throughout the development of version 4.0, check out the release notes.

Mozilla was originally planning on having Firefox 4 out by the end of last year, but it has had to delay the release multiple times. The company has fixed more than 7,000 bugs in the 12 betas and a few more in the two RC builds.

Mozilla has been struggling to get Firefox 4.0 out the door. As a result, the company has announced that in 2011, not only will we see Firefox 4.0, but we will also see Firefox 5.0, Firefox 6.0, and Firefox 7.0. The first 5.0 builds are already in the making; the next version is targeted for a late June 2011 release.





User Comments: 21

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treeski treeski said:

If you have a previous build of Firefox 4 and navigate to the Help>About page, it will automatically download the update and bring the software up to the release version.

Guest said:

If you want to save tabs when closing firefox.

browser.showQuitWarning - set it to True

Burty117 Burty117, TechSpot Chancellor, said:

Guest said:

If you want to save tabs when closing firefox.

browser.showQuitWarning - set it to True

I wish there was a Like button for this.

Guest said:

Is there a way to make sure all your add ons are compatible before you upgrade? I usually hold off for a month or so to give them time but if I knew for sure I would upgrade now.

Puiu Puiu said:

when you close firefox 4 the tabs are saved.

you have a button on the homepage which will restore them when you open FF again.

About the addons - go to and manually check if the addon supports FF4. if not then check if a beta version of the addon is available. (example: FEBE, firebug - beta stage but work just fine). if you find nothing then just force FF to install it. many addons still work even if there is no new version for FF4

Guest said:

Addon Compatibility Reporter

jackmitch said:

Awesome, i've been waiting on this for ages now!

Darkshadoe Darkshadoe said:

My Firefox updated to from 4.0 RC to 4.0 on Saturday for some reason. I found it kinda odd but im not complaining

Darkshadoe Darkshadoe said:

Sorry forgot to post a pic

Guest said:

You can get your tabs by clicking on history, then restore previous session.

Puiu Puiu said:

darkshadoe said:

My Firefox updated to from 4.0 RC to 4.0 on Saturday for some reason. I found it kinda odd but im not complaining

It was RC2 but when you look at the "About Firefox" it just said 4.0 . maybe because they were preparing for 4.0 but they were forced to push a second RC and they didn't have time to change that (or just forgot about it)

Darkshadoe Darkshadoe said:

puiu said:

darkshadoe said:

My Firefox updated to from 4.0 RC to 4.0 on Saturday for some reason. I found it kinda odd but im not complaining

It was RC2 but when you look at the "About Firefox" it just said 4.0 . maybe because they were preparing for 4.0 but they were forced to push a second RC and they didn't have time to change that (or just forgot about it)

I bet your right..I thought it was kinda strange them releasing it so soon..thx.

Gars Gars said:

Chrome is still faster

LNCPapa LNCPapa said:

I abandoned Firefox in the early 3.x days because it seemed to get slower and heavier with each release. This version... I actually like. Now my browser hierarchy goes Chrome>Firefox4.x>IE9>Opera>IE8>IE7>Firefo
3.x>Safari

yowanvista yowanvista said:

Waiting for FF5.0 beta

captaincranky captaincranky, TechSpot Addict, said:

I abandoned Firefox in the early 3.x days because it seemed to get slower and heavier with each release. This version... I actually like. Now my browser hierarchy goes Chrome>Firefox4.x>IE9>Opera>IE8>IE7>Firefo
3.x>Safari
Is there actually a point there somewhere? It seems like you might waste more time deciding which browser to launch, than any possible speed gains you might achieve by your decision.

Captaincranky says, "Chrome is only good for motorcycle parts, just say "no" to it as a web browser"!

Archean Archean, TechSpot Paladin, said:

Hey Cap !

Luckily my choices are rather limited to two options only i.e. IE9 & FF4. So I don't have to go through all the list LNC have; save lots of time I bet.

lawfer, TechSpot Paladin, said:

LNCPapa said:

I abandoned Firefox in the early 3.x days because it seemed to get slower and heavier with each release. This version... I actually like. Now my browser hierarchy goes Chrome>Firefox4.x>IE9>Opera>IE8>IE7>Firefo
3.x>Safari

I'm sorry, but did you really put IE7, and IE8 before Firefox 3.x? Hahaha, GTFO.

LNCPapa LNCPapa said:

Yeah, I did. As I stated I really disliked the FF3.x releases. I much preferred IE 7 and 8 over FF.

Nestea said:

It's Fx anyway.

I don't know why anyone would use IE. Their zone security is a joke. The only good thing is you get to see what cookies a website is setting and maybe for corporations it's easier to manage (restrict access).

Guest said:

Crashed three times in 1 hour :( [on google maps]

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