firefoxMozilla has launched Firefox 21 for Mac, Windows, and Linux, adding a number of improvements, namely to the browser's Social API.

The Social API is designed to allow social providers to integrate directly with Firefox, displaying selected content on the browser's sidebar or toolbar.

With the update Mozilla has added several new partners, including Cliqz, Mixi, and msnNow. Cliqz and msnNow are news aggregation services, while Mixi is Japan's largest social network.

Firefox 21 brings an enhanced UI for the Do Not Track Feature and preliminary implementation of the Firefox Health Report, which is a system that is designed to log browser health information like start up time, total running time, and number of crashes. It is designed to monitor browser performance and provide tools to fix potential problems. The update also includes a number of small changes and bug fixes, which can be found in the release notes.

Firefox 21 for the Mac is available for download from the Mozilla website.

Top Rated Comments

mrgraff Avatar
164 months ago
Before anybody thinks this is a big deal, don't forget that Firefox 22 will be released later this week also.
Score: 26 Votes (Like | Disagree)
roadbloc Avatar
164 months ago
Yes. Changing the first number implies that it's such a big leap that existing compatible software has a good chance of no longer being compatible. Changing the second number implies that that new features have been added, but compatible software that was working will continue to work. Changing the third number implies that no new features have been added, but existing features have been fixed.

From the sounds of it, most of these first number changes should actually be second number changes - new features are being tacked on but they aren't tearing apart existing APIs and starting over.

Its just a number. Breathe. Take a walk maybe.
Score: 7 Votes (Like | Disagree)
C DM Avatar
164 months ago
Before anybody thinks this is a big deal, don't forget that Firefox 22 will be released later this week also.
Try 6 weeks.

It's just a crazy idea that software, especially something like a browser, which is there to support ever changing technologies, should be updated and improved (in one way or another) on a regular and not-so-long intervals, right? :rolleyes:

----------

I agree. Surely a better naming system MUST exist?? When will it end?! I don't think anyone wants to have a version number in the 100's.
Why? Does the version number really matter somehow? Does it make the application, or really anything, worse in some way if it's on version 34 (or even 112) compared to 10.6.12?

----------

Google Chrome is at v.26, no one complains about that. Mozilla used to be slow on updates and people criticized their lack of keeping pace. Few use IE and Safari point releases are mostly for security issues alone. Why do we dislike rapid Firefox releases?
It's one of those "haters gonna hate" type of things--troll-like at worst, and maybe an inconsequential personal preference at best (which is still pretty much pointless in general).
Score: 6 Votes (Like | Disagree)
Simplicated Avatar
164 months ago
Google Chrome is at v.26, no one complains about that. Mozilla used to be slow on updates and people criticized their lack of keeping pace. Few use IE and Safari point releases are mostly for security issues alone. Why do we dislike rapid Firefox releases?

Or alternatively, why are we glorifying almost everything Google does?
Score: 6 Votes (Like | Disagree)
vsthsd Avatar
164 months ago
Google Chrome is at v.26, no one complains about that. Mozilla used to be slow on updates and people criticized their lack of keeping pace. Few use IE and Safari point releases are mostly for security issues alone. Why do we dislike rapid Firefox releases?
Score: 6 Votes (Like | Disagree)
ArtOfWarfare Avatar
164 months ago
Why? Does the version number really matter somehow? Does it make the application, or really anything, worse in some way if it's on version 34 (or even 112) compared to 10.6.12?

Yes. Changing the first number implies that it's such a big leap that existing compatible software has a good chance of no longer being compatible. Changing the second number implies that that new features have been added, but compatible software that was working will continue to work. Changing the third number implies that no new features have been added, but existing features have been fixed.

From the sounds of it, most of these first number changes should actually be second number changes - new features are being tacked on but they aren't tearing apart existing APIs and starting over.
Score: 5 Votes (Like | Disagree)

Popular Stories

iPhone Pocket Short

iPhone Pocket is Now Completely Sold Out Worldwide

Tuesday November 25, 2025 7:16 am PST by
Apple recently teamed up with Japanese fashion brand ISSEY MIYAKE to create the iPhone Pocket, a limited-edition knitted accessory designed to carry an iPhone. However, it is now completely sold out in all countries where it was released. iPhone Pocket became available to order on Apple's online store starting Friday, November 14, in the United States, France, China, Italy, Japan, Singapore, ...
iOS 26

When Will Apple Release iOS 26.2?

Monday December 1, 2025 4:37 pm PST by
We're getting closer to the launch of the final major iOS update of the year, with Apple set to release iOS 26.2 in December. We've had three betas so far and are expecting a fourth beta or a release candidate this week, so a launch could follow as soon as next week. Past Launch Dates Apple's past iOS x.2 updates from the last few years have all happened right around the middle of the...
Sad Siri Feature

Apple AI Chief John Giannandrea Retiring After Siri Delays

Monday December 1, 2025 2:16 pm PST by
Apple AI chief John Giannandrea is stepping down from his position and retiring in spring 2026, Apple announced today. Giannandrea will serve as an advisor between now and 2026, with former Microsoft AI researcher Amar Subramanya set to take over as vice president of AI. Subramanya will report to Apple engineering chief Craig Federighi, and will lead Apple Foundation Models, ML research, and ...
Netflix Smaller 4

Netflix Kills Casting From Its Mobile App to Most Modern TVs

Monday December 1, 2025 4:36 am PST by
Netflix has quietly removed the ability to cast content from its mobile apps to most modern TVs and streaming devices, including newer Chromecast models and the Google TV Streamer. The change was first spotted by users on Reddit and confirmed in an updated Netflix support page (via Android Authority), which now states that the streaming service no longer supports casting from mobile devices...
Cyber Week Deals 2025

Best Cyber Week Apple Deals Include Big Discounts on AirPods, Apple Watch, and More

Sunday November 30, 2025 7:33 am PST by
Cyber Week is here, and you can find popular Apple products like AirPods, iPad, Apple Watch, and more at all-time low prices. In this article, the majority of the discounts will be found on Amazon. Note: MacRumors is an affiliate partner with some of these vendors. When you click a link and make a purchase, we may receive a small payment, which helps us keep the site running. Specifically,...
maxresdefault

iPhone Fold: Launch, Pricing, and What to Expect From Apple's Foldable

Monday December 1, 2025 3:00 am PST by
Apple is expected to launch a new foldable iPhone next year, based on multiple rumors and credible sources. The long-awaited device has been rumored for years now, but signs increasingly suggest that 2026 could indeed be the year that Apple releases its first foldable device. Subscribe to the MacRumors YouTube channel for more videos. Below, we've collated an updated set of key details that ...
studio display purple february

M5 iPad Pro Could Hint at New Studio Display Feature

Sunday November 30, 2025 10:30 am PST by
The updated specs of the M5 iPad Pro may point toward a major new feature for Apple's next-generation Studio Display expected in early 2026. Apple's latest iPad Pro debuted last month and contains one display-related change that stands out: it can now drive external monitors at up to 120Hz with Adaptive Sync. The feature should deliver lower latency, smoother motion, and fewer visual...
New Intel Logo

Apple and Intel Rumored to Partner on Mac Chips Again in a New Way

Friday November 28, 2025 7:33 am PST by
While all Macs are now powered by Apple's custom-designed chips, a new rumor claims that Apple may rekindle its partnership with Intel, albeit in a new and limited way. Apple supply chain analyst Ming-Chi Kuo today said Intel is expected to begin shipping Apple's lowest-end M-series chip as early as mid-2027. Kuo said Apple plans to utilize Intel's 18A process, which is the "earliest...
Touchscreen MacBook Feature

Here Are the Four MacBooks Apple Is Expected to Launch Next Year

Monday December 1, 2025 5:00 am PST by
2026 could be a bumper year for Apple's Mac lineup, with the company expected to announce as many as four separate MacBook launches. Rumors suggest Apple will court both ends of the consumer spectrum, with more affordable options for students and feature-rich premium lines for users that seek the highest specifications from a laptop. Below is a breakdown of what we're expecting over the next ...
iphone black friday gold

The Best Black Friday iPhone Deals Still Available

Friday November 28, 2025 6:24 am PST by
Cellular carriers have always offered big savings on the newest iPhone models during the holidays, and Black Friday 2025 sales have kicked off at AT&T, Verizon, T-Mobile, and more. Right now we're tracking notable offers on the iPhone 17, iPhone 17 Pro, iPhone 17 Pro Max, and iPhone Air. For even more savings, keep an eye on older models during the holiday shopping season. Note: MacRumors is...