After 12 betas, two release candidates and more than nine months of development,
Mozilla today officially released its next generation open source Firefox 4
Web browser.
With Firefox 4 — the first major browser update since Mozilla
released Firefox 3.6 in
January of 2010 — developers have made multiple user-facing changes that will
noticed quickly by Firefox veterans. Tabs are now on top of the address bar
by default, instead of below it as they have been since Firefox was
first conceived.
The user
interface
itself has been revamped in an effort to reduce clutter.
“We spent a bunch of time on the interface, making it as streamlined as possible,
making it easy to get to the things that you want and also easy to get things
out of your way,” Johnathan Nightingale, director of Firefox at Mozilla, told InternetNews.com. “Moving
from Firefox 3.6 to 4.0, we’ve compacted the interface, since most of the time
users don’t need the whole menu.”
The “home” button has been moved to the right of the address bar and the RSS icon has also been removed from the default display. Nightingale stressed that Mozilla has not taken any functionality away from the browser. It has just moved items from the default display in an effort to improve usability and efficiency.
Firefox 4 also integrates the Firefox Sync technology, which enables users to synchronize their browser tabs and history across multiple systems. Firefox Sync extends to mobile platforms including Apple’s iOS by way of the Firefox Home application.
Another key aspect of usability is the new Panorama feature, which enables
users to group tabs together. Mozilla also looked to improve tabs with the
addition of the a App Tab feature that pins a tab to the left of the browser.
“App Tabs is a recognition that the way people use the Web today is different,” Nightingale
said. “Something like Gmail is not simply a Web page that a user opens then
closes, it’s an application that happens to live on the Web.”
Another tab improvement is delivered by way of a notification element. If
something has changed within an App Tab in Firefox 4, a blue glow
appears
around the favicon. For example, if a user has a Gmail App Tab, whenever
new email is received the tab will have a blue glow.
Mozilla’s extension system has also undergone a dramatic change in Firefox 4. The new browser makes use of the new Mozilla Jetpack platform, which enables users to install and run extensions without the need to reload the browser.
For developers, Jetpack also makes it easier to build extensions by using JavaScript.
>”You don’t have to learn XUL, you can just pull in some JavaScript APIs that feel a lot like Web-based platforms,” Nightingale said.
Nightingale said that extensions that were not built with Jetpack will still also run in Firefox 4. Mozilla’s add-ons site does identify which extensions require a restart and which ones do not.
On the security front, Firefox 4 includes Mozilla’s Do
Not Track implementation.
With Do Not Track, browser users are able to alert sites whether or not they
want to be tracked. However, it is still up to the Web sites themselves to
actually add support for the specification. Both Google Chrome and Microsoft’s
IE 9 each has its own respective versions of a Do Not Track feature.
There is also a new Content Security Policy feature in Firefox 4 that could potentially mitigate most of the risk associated with Cross Site Scripting (XSS) attacks.
“Content Security Policy lets sites say where they expect to be loading content from,” Nightingale said. “So if script is loaded from somewhere else, it’s likely a XSS vulnerability on the Web site.”
Mozilla’s Nighingale said that CSP enables Web sites to block non-authorized
JavaScript. Additionally, the system can report unauthorized script usage..
“The reporting aspect means that every Firefox 4 users makes the Web safer,” Nightingale said. “If a Firefox 4 user is the first one to see an unauthorized script, we’ll send back the ping and the site can see that and they can fix the bug.”
The other key new security features is HTTP Strict Transport Security (HSTS),
which can force SSL security to be used. The HSTS feature is important as it
can help protect users against potential credential-sniffing attacks such as
the one propagated by Firesheep earlier this year.
Mozilla developers have also been determined to ensure that Firefox 4 is the fastest browser available. To accomplish that goal, developers enhanced the JagerMonkey JavaScript engine in an effort to boost performance.
Having a fast browsing experience all begins with how fast the browser starts, which is also an area of improvement in Firefox 4.
“We’re not interested in optimizing for a specific benchmark, but we’re very interested in optimizing for common workloads,” Nightingale said.
Sean Michael Kerner is a senior editor at InternetNews.com, the news service of Internet.com, the network for technology professionals.
Huawei’s AI Update: Things Are Moving Faster Than We Think
FEATURE | By Rob Enderle,
December 04, 2020
Keeping Machine Learning Algorithms Honest in the ‘Ethics-First’ Era
ARTIFICIAL INTELLIGENCE | By Guest Author,
November 18, 2020
Key Trends in Chatbots and RPA
FEATURE | By Guest Author,
November 10, 2020
FEATURE | By Samuel Greengard,
November 05, 2020
ARTIFICIAL INTELLIGENCE | By Guest Author,
November 02, 2020
How Intel’s Work With Autonomous Cars Could Redefine General Purpose AI
ARTIFICIAL INTELLIGENCE | By Rob Enderle,
October 29, 2020
Dell Technologies World: Weaving Together Human And Machine Interaction For AI And Robotics
ARTIFICIAL INTELLIGENCE | By Rob Enderle,
October 23, 2020
The Super Moderator, or How IBM Project Debater Could Save Social Media
FEATURE | By Rob Enderle,
October 16, 2020
FEATURE | By Cynthia Harvey,
October 07, 2020
ARTIFICIAL INTELLIGENCE | By Guest Author,
October 05, 2020
CIOs Discuss the Promise of AI and Data Science
FEATURE | By Guest Author,
September 25, 2020
Microsoft Is Building An AI Product That Could Predict The Future
FEATURE | By Rob Enderle,
September 25, 2020
Top 10 Machine Learning Companies 2020
FEATURE | By Cynthia Harvey,
September 22, 2020
NVIDIA and ARM: Massively Changing The AI Landscape
ARTIFICIAL INTELLIGENCE | By Rob Enderle,
September 18, 2020
Continuous Intelligence: Expert Discussion [Video and Podcast]
ARTIFICIAL INTELLIGENCE | By James Maguire,
September 14, 2020
Artificial Intelligence: Governance and Ethics [Video]
ARTIFICIAL INTELLIGENCE | By James Maguire,
September 13, 2020
IBM Watson At The US Open: Showcasing The Power Of A Mature Enterprise-Class AI
FEATURE | By Rob Enderle,
September 11, 2020
Artificial Intelligence: Perception vs. Reality
FEATURE | By James Maguire,
September 09, 2020
Anticipating The Coming Wave Of AI Enhanced PCs
FEATURE | By Rob Enderle,
September 05, 2020
The Critical Nature Of IBM’s NLP (Natural Language Processing) Effort
ARTIFICIAL INTELLIGENCE | By Rob Enderle,
August 14, 2020
Datamation is the leading industry resource for B2B data professionals and technology buyers. Datamation's focus is on providing insight into the latest trends and innovation in AI, data security, big data, and more, along with in-depth product recommendations and comparisons. More than 1.7M users gain insight and guidance from Datamation every year.
Advertise with TechnologyAdvice on Datamation and our other data and technology-focused platforms.
Advertise with Us
Property of TechnologyAdvice.
© 2025 TechnologyAdvice. All Rights Reserved
Advertiser Disclosure: Some of the products that appear on this
site are from companies from which TechnologyAdvice receives
compensation. This compensation may impact how and where products
appear on this site including, for example, the order in which
they appear. TechnologyAdvice does not include all companies
or all types of products available in the marketplace.