Firefox

This article is about the web browser. For other uses, seeFirefox (disambiguation).

"Phoenix (web browser)" redirects here. For the early-1990s web browser developed at the University of Chicago, seePhoenix (tkWWW-based browser).

Firefox

Logo used since October 2019
Developer(s)	Mozilla Foundationand its contributors Mozilla Corporation
Initial release	November 9, 2004(2004-11-09)
Stable release(s)[±]
Standard 128.0/ July 9, 2024(July 9, 2024) Extended support release 1 128.0esr/ July 9, 2024(July 9, 2024) Extended support release 2 115.13.0esr/ July 9, 2024(2024-07-09)
Preview release(s)[±]
Beta & developer edition 129.0b4/ July 15, 2024(July 15, 2024) Nightly 130.0a1/ July 9, 2024(July 9, 2024)
Repository	hg.mozilla.org/mozilla-central/
Written in	C++,JavaScript,HTML,C,Rust,and others
Engines	Gecko,Quantum,andSpiderMonkey;WebKiton iOS
Operating system	Linux macOS 10.15or later Windows 10or later Android 5.0or later iOS 15.0or later
Included with	VariousUnix-likeoperating systems
Available in	97 languages
Type	Web browser
License	MPL 2.0
Website	mozilla.org/firefox

Mozilla Firefox,or simplyFirefox,is afree and open-sourceweb browserdeveloped by theMozilla Foundationand its subsidiary, theMozilla Corporation.It uses theGeckorendering engineto display web pages, which implements current and anticipated web standards.Firefox is available forWindows 10or later versions,macOS,andLinux.Its unofficial portsare available for variousUnixandUnix-likeoperating systems, includingFreeBSD,OpenBSD,NetBSD,and other platforms. It is also available forAndroidandiOS.However, as with all other iOS web browsers, the iOS version uses theWebKitlayout engine instead of Gecko due to platform requirements. An optimized version is also available on theAmazon Fire TVas one of the two main browsers available withAmazon's Silk Browser.

Firefox is thespiritual successorofNetscape Navigator,as theMozillacommunity was created byNetscapein 1998, before its acquisition byAOL.Firefox was created in 2002 under the codename "Phoenix" by members of the Mozilla community who desired a standalone browser rather than theMozilla Application Suitebundle. During itsbetaphase, it proved to be popular with its testers and was praised for its speed, security, and add-ons compared toMicrosoft's then-dominantInternet Explorer 6.It was released on November 9, 2004,and challengedInternet Explorer's dominance with 60 million downloads within nine months.In November 2017, Firefox began incorporating new technology under the code name "Quantum"to promoteparallelismand a more intuitiveuser interface.

Firefox usage share grew to a peak of 32.21% in November 2009,withFirefox 3.5overtakingInternet Explorer 7,although not all versions of Internet Explorer as a whole;its usage then declined in competition withGoogle Chrome.As of December 2023,according toStatCounter,it had a 6.7% usage share on traditional PCs (i.e. as a desktop browser), making it the fourth-most popular PC web browser after Google Chrome (62%),Safari(13%), andMicrosoft Edge(11%).

History

See also:Firefox early version historyandFirefox version history

The project began as an experimental branch of theMozilla projectbyDave Hyatt,Joe Hewitt,andBlake Ross.They believed the commercial requirements ofNetscape's sponsorship and developer-drivenfeature creepcompromised the utility of the Mozilla browser.To combat what they saw as theMozilla Suite'ssoftware bloat,they created a standalone browser, with which they intended to replace the Mozilla Suite.Version 0.1 was released on September 23, 2002.On April 3, 2003, theMozilla Organizationannounced that it planned to change its focus from the Mozilla Suite to Firefox andThunderbird.

Screenshot of Phoenix 0.1 onWindows XP

The Firefox project has undergone several name changes.The nascent browser was originally named Phoenix, after themythical birdthat rose triumphantly from the ashes of its dead predecessor (in this case, from the "ashes" ofNetscape Navigator,after it was sidelined by Microsoft Internet Explorer in the "First Browser War"). Phoenix was renamed in 2003 due to a trademark claim fromPhoenix Technologies.The replacement name, Firebird, provoked an intense response from theFirebirddatabase software project.The Mozilla Foundation reassured them that the browser would always bear the name Mozilla Firebird to avoid confusion. After further pressure, Mozilla Firebird became Mozilla Firefox on February 9, 2004.The name Firefox was said to be derived from a nickname of thered panda,which became the mascot for the newly named project.For the abbreviation of Firefox, Mozilla prefersFxorfx,although it is often abbreviated asFF.

The Firefox project went through many versions before version 1.0 and had already gained a great deal of acclaim from numerous media outlets, such asForbesandThe Wall Street Journal.Among Firefox's popular features were the integratedpop-up blocker,tabbed browsing,and an extension mechanism for adding functionality. Although these features have already been available for some time in other browsers such as theMozilla SuiteandOpera,Firefox was the first of these browsers to have achieved large-scale adoption.Firefox attracted attention as an alternative toInternet Explorer,which had come under fire for its alleged poor program design and insecurity—detractors cite IE's lack of support for certain Web standards, use of the potentially dangerousActiveXcomponent, and vulnerability to spyware and malware installation.Microsoft responded by releasingWindows XPService Pack 2, which added several important security features to Internet Explorer 6.

Version 1.0 of Firefox was released on November 9, 2004.This was followed by version 1.5 in November 2005, version 2.0 in October 2006, version 3.0 in June 2008, version 3.5 in June 2009, version 3.6 in January 2010, and version 4.0 in March 2011. From version 5 onwards, the development and release model changed into a "rapid" one; by the end of 2011 the stable release was version 9, and by the end of 2012 it reached version 17.

Major redesigns of itsgraphical user interfaceoccurred on versions 4.0 (Strata) in March 2011, 29.0 (Australis) in April 2014, 57.0 (Photon) in November 2017, and 89.0 (Proton) in June 2021.

In 2016, Mozilla announced a project known asQuantum,which sought to improve Firefox's Gecko engine and other components to improve the browser's performance, modernize its architecture, and transition the browser to amulti-processmodel. These improvements came in the wake of decreasing market share toGoogle Chrome,as well as concerns that its performance was lapsing in comparison. Despite its improvements, these changes required existingadd-onsfor Firefox to be made incompatible with newer versions, in favor of a newextensionsystem that is designed to be similar to Chrome and other recent browsers. Firefox 57, which was released in November 2017, was the first version to contain enhancements from Quantum, and has thus been namedFirefox Quantum.A Mozilla executive stated that Quantum was the "biggest update" to the browser since version 1.0.Unresponsive and crashing pages only affect other pages loaded within the same process. While Chrome uses separate processes for each loaded tab, Firefox distributes tabs over four processes by default (since Quantum), in order to balance memory consumption and performance. The process count can be adjusted, where more processes increase performance at the cost of memory, therefore suitable for computers with larger RAM capacity.

On May 3, 2019, the expiration of an intermediate signing certificate on Mozilla servers caused Firefox to automatically disable and lock all browser extensions (add-ons).Mozilla began the roll-out of a fix shortly thereafter, using their Mozilla Studies component.

Support forAdobe Flashwas dropped on January 6, 2021, with the release of Firefox 85.

On June 1, 2021, Firefox's 'Proton' redesign was offered through its stable release channelafter being made available in the beta builds.While users were initially allowed to revert to the old design throughabout:config,the correspondingkey-value pairsreportedly stopped working in future builds, resulting in criticism.These included accessibility concernsdespite Mozilla's claim to "continue to work with the accessibility community"and are continuing issues.

On January 13, 2022, an issue with Firefox's HTTP/3 implementation resulted in a widespread outage for multiple hours.

On September 26, 2023, Firefox 118.0 introduced on-device translation of web page content.

On January 23, 2024, along with the release of Firefox 122.0, Mozilla introduced an officialAPT repositoryforDebian-basedLinux distributions.

Features

Main article:Features of Firefox

Features of the desktop edition includetabbed browsing,full-screen mode,spell checking,incremental search,smart bookmarks,bookmarking and downloading throughdrag and drop,adownload manager,user profilemanagement,private browsing,bookmark tags, bookmarkexporting,offline mode,ascreenshottool,web development tools,a "page info" feature which shows a list of page metadata and multimedia items,a configuration menu atabout:configforpower users,and location-aware browsing (also known as "geolocation") based on a Google service.Firefox has an integrated search system which uses Google by default in most markets.DNS over HTTPSis another feature whose default behaviour is determined geographically.

Firefox provides an environment for web developers in which they can use built-in tools, such as the Error Console or theDOM Inspector,andextensions,such asFirebugand more recently there has been an integration feature withPocket.Firefox Hello was an implementation ofWebRTC,added in October 2014, which allows users of Firefox and other compatible systems to have a video call, with the extra feature of screen and file sharing by sending a link to each other. Firefox Hello was scheduled to be removed in September 2016.

Former features include aFile Transfer Protocol(FTP) client for browsing file servers, the ability to block images from individual domains (until version 72),a3D page inspector(versions 11 to 46), tab grouping (until version 44), and the ability to add customized extra toolbars (until version 28).

Browser extensions

Functions can be added throughadd-onscreated bythird-party developers.Add-ons are primarily coded using anHTML,CSS,JavaScript,withAPIknown asWebExtensions,which is designed to be compatible withGoogle ChromeandMicrosoft Edgeextension systems.Firefox previously supported add-ons using theXULandXPCOMAPIs, which allowed them to directly access and manipulate much of the browser's internal functionality. As compatibility was not included in the multi-process architecture, XUL add-ons have been deemedLegacy add-onsand are no longer supported on Firefox 57 "Quantum" and newer.

Mozilla has occasionally installed extensions for users without their permission. This happened in 2017 when an extension designed to promote the showMr. Robotwas silently added in an update to Firefox.

Themes

Firefox can have themes added to it, which users can create or download from third parties to change the appearance of the browser.

Guest session

In 2013, Firefox for Android added aguest sessionmode, which wiped browsing data such as tabs, cookies, and history at the end of each guest session. Guest session data was kept even when restarting the browser or device, and deleted only upon a manual exit. The feature was removed in 2019, purportedly to "streamline the experience".

Standards

The result of theAcid3test on Firefox 17

Firefox implements manyweb standards,includingHTML4(almost fullHTML5),XML,XHTML,MathML,SVG1.1 (full),SVG 2 (partial),CSS(with extensions),ECMAScript (JavaScript),DOM,XSLT,XPath,andAPNG(AnimatedPNG) images withAlpha transparency.Firefox also implements standards proposals created by theWHATWGsuch as client-side storage,and thecanvas element.These standards are implemented through the Gecko layout engine, andSpiderMonkeyJavaScript engine. Firefox 4 was the first release to introduce significant HTML5 and CSS3 support.

Firefox has passed theAcid2standards-compliance test since version 3.0.Mozilla had originally stated that they did not intend for Firefox to pass theAcid3test fully because they believed that the SVG fonts part of the test had become outdated and irrelevant, due toWOFFbeing agreed upon as a standard by all major browser makers.Because the SVG font tests were removed from the Acid3 test in September 2011, Firefox 4 and greater scored 100/100.

Firefox also implements "Safe Browsing,"aproprietary protocolfrom Google used to exchange data related with phishing and malware protection.

Firefox supports the playback of video content protected by HTML5Encrypted Media Extensions(EME), since version 38. For security and privacy reasons, EME is implemented within a wrapper of open-source code that allows execution of aproprietaryDRMmodule byAdobe Systems—Adobe Primetime Content Decryption Module (CDM). CDM runs within a "sandbox"environment to limit its access to the system and provide it a randomized device ID to prevent services fromuniquely identifying the devicefor tracking purposes. The DRM module, once it has been downloaded, is enabled, and disabled in the same manner as otherplug-ins.Since version 47,"Google's Widevine CDM on Windows and Mac OS X so streaming services likeAmazon Videocan switch fromSilverlightto encrypted HTML5 video "is also supported. Mozilla justified its partnership with Adobe and Google by stating:

Firefox downloads and enables the Adobe Primetime and Google Widevine CDMs by default to give users a smooth experience on sites that require DRM. Each CDM runs in a separate container called a sandbox and you will be notified when a CDM is in use. You can also disable each CDM and opt-out of future updates

— Watch DRM content on Firefox

and that it is "an important step on Mozilla's roadmap to removeNPAPIplugin support. "Upon the introduction of EME support, builds of Firefox on Windows were also introduced that exclude support for EME.TheFree Software FoundationandCory Doctorowcondemned Mozilla's decision to support EME.

Security

See also:Browser security

From its inception, Firefox was positioned as a security-focused browser. At the time,Internet Explorer,the dominant browser, was facing a security crisis. Multiple vulnerabilities had been found, andmalwarelikeDownload.Jectcould be installed simply by visiting a compromised website. The situation was so bad that the US Government issued a warning against using Internet Explorer.Firefox, being less integrated with the operating system, was considered a safer alternative since it was less likely to have issues that could completely compromise a computer. This led to a significant increase in Firefox's popularity during the early 2000s as more secure alternative.Moreover, Firefox was considered to have fewer actively exploitablesecurity vulnerabilitiescompared to its competitors. In 2006,The Washington Postreported that exploit code for known security vulnerabilities in Internet Explorer were available for 284 days compared to only nine days for Firefox before the problem was fixed.ASymantecstudy around the same period showed that even though Firefox had a higher number of vulnerabilities, on average vulnerabilities were fixed faster in Firefox than in other browsers during that period.

During this period, Firefox used amonolithic architecture,like most browsers at the time. This meant all browser components ran in a singleprocesswith access to allsystem resources.This setup had multiple security issues. If a web page used too many resources, the entire Firefox process would hang or crash, affecting all tabs. Additionally, any exploit could easily access system resources, including user files. Between 2008 and 2012, most browsers shifted to a multiprocess architecture, isolating high-risk processes like rendering, media, GPU, and networking.However, Firefox was slower to adopt this change. It wasn't until 2015 that Firefox started its Electrolysis (e10s) project to implement sandbo xing across multiple components. This rewrite relied oninterprocess communicationusingChromium's interprocess communication library and placed various component including the rendering component in its own sandbox.Firefox released this rewrite in to beta in August 2016, noting a 10-20% increase in memory usage, which was lower than Chrome's at the time.However, the rewrite caused issues with their legacy extension API, which was not designed to work cross-process and requiredshim codeto function correctly.After over a year in beta, the rewrite was enabled by default all users of Firefox in November 2017.

In 2012, Mozilla launched a new project calledServoto write a completely new and experimental browser engine utilizingmemory safetechniques written inRust.In 2018, Mozilla opted to integrate parts of the Servo project into theGecko enginein a project codenamed the Quantum project.The project completely overhauled Firefox's page rendering code resulting in performance and stability gains while also improving the security of existing components.Additionally, the older incompatible extension API was removed in favour of aWebExtension APIthat more closely resembled Google Chrome's extension system. This broke compatibility with older extensions but resulted in lesser vulnerabilities and a much more maintainable extension system.While the Servo project was intended to replace more parts of the Gecko Engine,this plan never came to fruition. In 2020, Mozilla laid off all developers on the Servo team transferring ownership of the project to theLinux Foundation.

Privacy

When Firefox initially released, it used a custom script permission policy where scripts that were signed by the page could gain access to higher privilege actions such as the ability to set a user's preferences. However, this model was not widely used and was later discontinued by Firefox. Modern day Firefox instead follows the standardsame-origin policypermission model that is followed by most modern browsers which disallows scripts from accessing any privileged data including data about other websites.

It usesTLSto protect communications with web servers using strongcryptographywhen using theHTTPSprotocol.The freely availableHTTPS Everywhereadd-on enforces HTTPS, even if a regular HTTPURLis entered. Firefox now supports HTTP/2.

In February 2013, plans were announced for Firefox 22 to disablethird-party cookiesby default. However, the introduction of the feature was then delayed so Mozilla developers could "collect and analyze data on the effect of blocking some third-party cookies." Mozilla also collaborated withStanford University's "Cookie Clearinghouse" project to develop ablacklistandwhitelistof sites that will be used in the filter.

Version 23, released in August 2013, followed the lead of its competitors by blockingiframe,stylesheet, and script resources served from non-HTTPS servers embedded on HTTPS pages by default. Additionally,JavaScriptcould also no longer be disabled through Firefox's preferences, and JavaScript was automatically re-enabled for users who upgraded to 23 or higher with it disabled. The change was made due to the fact the JavaScript was being used across a majority of websites on the web and disabling JavaScript could potentially have untoward repercussions on inexperienced users who are unaware of its impact. Firefox also cited the fact that extensions likeNoScript,that can disable JavaScript in a more controlled fashion were widely available. The following release added the ability to disable JavaScript through the developer tools for testing purposes.

Beginning with Firefox 48, all extensions must be signed by Mozilla to be used in release and beta versions of Firefox. Firefox 43 blocked unsigned extensions but allowed enforcement of extension signing to be disabled. All extensions must be submitted toMozilla Add-onsand be subject to code analysis in order to be signed, although extensions do not have to be listed on the service to be signed.On May 2, 2019, Mozilla announced that it would be strengthening the signature enforcement with methods that included the retroactive disabling of old extensions now deemed to be insecure.

Since version 60 Firefox includes the option to useDNS over HTTPS(DoH), which causesDNS lookuprequests to be sent encrypted over the HTTPS protocol.To use this feature the user must set certain preferences beginning with "network.trr" (Trusted Recursive Resolver) inabout:config:if network.trr.mode is 0, DoH is disabled; 1 activates DoH in addition to unencrypted DNS; 2 causes DoH to be used before unencrypted DNS; to use only DoH, the value must be 3. By setting network.trr.uri to the URL, specialCloudflareservers will be activated. Mozilla has a privacy agreement with this server host that restricts their collection of information about incoming DNS requests.

On May 21, 2019, Firefox was updated to include the ability to block scripts that used a computer'sCPUto minecryptocurrencywithout a user's permission, in Firefox version 67.0. The update also allowed users to block knownfingerprintingscripts that track their activity across the web, however it does not resist fingerprinting on its own.

In March 2021, Firefox launched SmartBlock in version 87 to offer protection againstcross-site tracking,without breaking the websites users visit.Also known as state partitioning or "total cookie protection", works via a feature in the browser that isolates data from each site visited by the user to ensure that cross-site scripting is very difficult if not impossible. The feature also isolates local storage, service workers and other common ways for sites to store data.

Localizations

Firefox is a widelylocalizedweb browser. Mozilla uses the in-house Pontoon localization platform.The first official release in November 2004 was available in 24 different languages and for 28locales.In 2019, Mozilla released Project Fluent a localization system that allows translators to be more flexible with their translation than to be constrained in one-to-one translation of strings.As of July 2024the supported versions of Firefox are available in 97 locales (88 languages).

Platform availability

The desktop version of Firefox is available and supports Microsoft Windows, macOS, and Linux, whileFirefox for Androidis available for Android (formerly Firefox for mobile, it also ran onMaemo,MeeGoandFirefox OS) andFirefox for iOSis available for iOS. Smartphones thatsupport Linuxbut do not support Android or iOS apps can also run Firefox in its desktop version, for example usingpostmarketOS.

Operating system		Latest stable version	Support status
Windows	10 v1709and later	Current stable version:128.0 (ARM64)	2019–
		Older version, yet still maintained:128.0esr (ARM64)
	10and later,Server 2016and later	Current stable version:128.0 (x64)	2015–
		Older version, yet still maintained:128.0esr (x64)
		Current stable version:128.0 (IA-32)
		Older version, yet still maintained:128.0esr (IA-32)
	7,Server 2008 R2,8,Server 2012, 8.1andServer 2012 R2	Older version, yet still maintained:115.13.0esr (x64)	2015–2024
		Older version, yet still maintained:115.13.0esr (IA-32)	2009–2024
	XP,Server 2003, VistaandServer 2008	Old version, no longer maintained:52.9.0esr (IA-32)	2004–2018
	2000	Old version, no longer maintained:10.0.12esr	2004–2013
		Old version, no longer maintained:12.0	2004–2012
	NT 4.0(IA-32),98andMe	Old version, no longer maintained:2.0.0.20	2004–2008
	95	Old version, no longer maintained:1.5.0.12	2004–2007
macOS	11(ARM64) and later	Current stable version:128.0	2020–
		Older version, yet still maintained:128.0esr
	10.15(x64) and later	Current stable version:128.0	2019–
		Older version, yet still maintained:128.0esr
	10.12–10.14	Older version, yet still maintained:115.13.0esr	2016–2024
	10.9–10.11	Old version, no longer maintained:78.15.0esr	2013–2021
	10.6–10.8	Old version, no longer maintained:45.9.0esr	2009–2017
		Old version, no longer maintained:48.0.2	2009–2016
	10.5(IA-32 and x64)	Old version, no longer maintained:10.0.12esr	2007–2013
		Old version, no longer maintained:16.0.2	2007–2012
	10.4(IA-32 and PPC)–10.5(PPC)	Old version, no longer maintained:3.6.28	2005–2012
	10.2–10.3	Old version, no longer maintained:2.0.0.20	2004–2008
	10.0–10.1	Old version, no longer maintained:1.0.8	2004–2006
Linux(X11/Wayland)		Current stable version:128.0 (x64)	2011–
		Older version, yet still maintained:128.0esr (x64)
		Current stable version:128.0 (IA-32)	2004–
		Older version, yet still maintained:128.0esr (IA-32)

Legend:

Old version

Older version, still maintained

Latest version

Latest preview version

Future release

Notes

• In March 2014, theWindows Store appversion of Firefox was cancelled, although there is a beta release.
• SSE2instruction set support is required for 49.0 or later forWindowsand 53.0 or later forLinux,IA-32 support only applies tosuperscalarprocessors.

Firefox source code may becompiledfor various operating systems; however, officially distributed binaries are provided for the following:

Required hardware and software

Requirement	Microsoft Windows	Linuxdesktop	macOS	Android	iOS
CPU	1GHz or faster compatible processor(orARM64for Windows) ESR:Pentium 4or newer withSSE2(or ARM64 for Windows)		Anyx86-64and ARM64 CPU	ARMv7,ARM64,IA-32andx64	ARM64
Memory (RAM)	1GBfor the 32-bit version and 2 GB for the 64-bit version ESR: 512MBfor the 32-bit version and 2 GB for the 64-bit version			384 MB	?
Data storage devicefree space	500 MB ESR: 200 MB			80 MB	~128 MB
Operating system	Windows 10or later Windows Server 2016or later ESR:Windows 7,Server 2008 R2,8,Server 2012,8.1andServer 2012 R2	Minimum GTK3.14 or newer libstdc++4.8.1 or newer X.Org1.0 or newer glibc2.17 or newer Recommended NetworkManager0.7 or newer DBus1.0 or newer GNOME2.16 or newer PulseAudio X.Org1.7 or newer libxtst 1.2.3 or newer	macOS 10.15or newer ESR:10.12–10.14	5.0or newer	iOS 15or later

Microsoft Windows

Firefox 1.0 was released forWindows 95,as well asWindows NT 4.0or later. Some users reported the 1.x builds were operable (but not installable) onWindows NT 3.51.

The version 42.0 release includes the firstx64build. It requiredWindows 7orServer 2008 R2.Starting from version 49.0, Firefox for Windows requires and uses theSSE2instruction set.

In September 2013, Mozilla released aMetro-style versionof Firefox, optimized fortouchscreenuse, on the "Aurora" release channel. However, on March 14, 2014, Mozilla cancelled the project because of a lack of user adoption.

In March 2017, Firefox 52 ESR, the last version of the browser forWindows XPandWindows Vista,was released.Support for Firefox 52 ended in June 2018.

Traditionally, installing the Windows version of Firefox entails visiting the Firefox website and downloading an installer package, depending on the desired localization and system architecture. In November 2021, Mozilla made Firefox available onMicrosoft Store.The Store-distributed package does not interfere with the traditional installation.

The last version of Firefox for Windows 7 and 8 is Firefox 115 ESR, which was released in July 2023.Itsend-of-lifeis planned to be in September 2024.

macOS

Firefox 57 onmacOS High Sierra

The first official release (Firefox version 1.0) supportedmacOS(then called Mac OS X) on thePowerPCarchitecture. Mac OS X builds for theIA-32architecture became available via auniversal binarywhich debuted with Firefox 1.5.0.2 in 2006.

Starting with version 4.0, Firefox was released for the x64 architecture to which macOS had migrated.Version 4.0 also dropped support for PowerPC architecture, although other projects continued development of a PowerPC version of Firefox.

Firefox was originally released for Mac OS X 10.0 and higher.The minimum OS then increased to Mac OS X 10.2 in Firefox 1.5 and 10.4 in Firefox 3.Firefox 4 dropped support for Mac OS X 10.4 and PowerPC Macs, and Firefox 17 dropped support for Mac OS X 10.5 entirely.The system requirements were left unchanged until 2016, when Firefox 49 dropped support for Mac OS X 10.6–10.8.Mozilla ended support for OS X 10.9–10.11 in Firefox 79, with those users being supported on the Firefox 78 ESR branch until November 2021.Most recently, Mozilla ended support formacOS 10.12–10.14in Firefox 116, with those users being supported on the Firefox 115 ESR branch until late 2024.

Linux

Firefox 96 onArch Linux

Opening Wikipedia main page with Mozilla Firefox 99 on Ubuntu 20.04

Since its inception, Firefox for Linux supported the 32-bit memory architecture of the IA-32 instruction set. 64-bit builds were introduced in the 4.0 release.The 46.0 release replacedGTK2.18 with 3.4 as a system requirement on Linux and other systems runningX.Org.Starting with 53.0, the 32-bit builds require theSSE2instruction set.

Firefox for Android

Main article:Firefox for Android

Firefox for mobile, code-named "Fennec", was first released forMaemoin January 2010 with version 1.0and forAndroidin March 2011 with version 4.0.Support for Maemo was discontinued after version 7, released in September 2011.Fennec had a user interface optimized for phones and tablets. It included the Awesome Bar, tabbed browsing, add-on support, a password manager, location-aware browsing, and the ability to synchronize with the user's other devices with Mozilla Firefox usingFirefox Sync.At the end of its existence, it had a market share of 0.5% on Android.

In August 2020, Mozilla launched a new version of itsFirefox for Androidapp, named Firefox Daylight to the publicand codenamedFenix,after a little over a year of testing.It boasted higher speeds with its newGeckoViewengine, which is described as being "the only independentweb engine browseravailable onAndroid".It also added Enhanced Tracking Protection 2.0, a feature that blocks many knowntrackerson the Internet.It also added the ability to place the address bar on the bottom, and a new Collections feature.However, it was criticized for only having nineAdd-onsat launch, and missing certain features.In response, Mozilla stated that they will allow more Add-ons with time.

Firefox onMeeGoOS

Firefox onFirefox OS

Firefox 115 onAndroid

Operating system		Latest stable version	Support status
Android (includingAndroid-x86)	5.0and later	Current stable version:128.0 (x64)	2018–
		Current stable version:128.0 (ARM64)	2017–
		Current stable version:128.0 (IA-32)	2014–
		Current stable version:128.0 (ARMv7)
	4.1–4.4	Old version, no longer maintained:68.11.0 (x64)	2018–2020
		Old version, no longer maintained:68.11.0 (IA-32)	2013–2020
		Old version, no longer maintained:68.11.0 (ARMv7)	2012–2020
	4.0	Old version, no longer maintained:55.0.2 (IA-32)	2013–2017
		Old version, no longer maintained:55.0.2 (ARMv7)	2011–2017
	3.0–3.2	Old version, no longer maintained:45.0.2 (ARMv7)	2011–2016
	2.3	Old version, no longer maintained:47.0 (ARMv7)
	2.2–4.3	Old version, no longer maintained:31.3.0esr (ARMv6)	2012–2015
	2.2	Old version, no longer maintained:31.0 (ARMv7)	2011–2014
	2.1	Old version, no longer maintained:19.0.2 (ARMv6)	2012–2013
		Old version, no longer maintained:19.0.2 (ARMv7)	2011–2013
	2.0	Old version, no longer maintained:6.0.2 (ARMv7)	2011
Firefox OS	2.2	Old version, no longer maintained:35/36/37	2015
	2.1	Old version, no longer maintained:33/34	2014–2015
	2.0	Old version, no longer maintained:31/32
Maemo		Old version, no longer maintained:7.0.1	2010–2011
Windows Mobile	6.x	Old version, no longer maintained:1.0a3	N/A

Legend:

Old version

Older version, still maintained

Latest version

Latest preview version

Future release

Notes

• Firefox for iOSis not listed in this table as its version numbers would be misleading. Prior to version 96it used version numbers that do not correspond to any of the other Firefox versions. Those share a core component, the Gecko rendering engine, and track its version numbers, whereas the version for theiOSoperating system uses the operating system's rendering engine (WebKit), rather than Mozilla's (Gecko).

Firefox for iOS

Mozilla initially refused to port Firefox to iOS, due to the restrictions Apple imposed on third-party iOS browsers. Instead of releasing a full version of the Firefox browser, Mozilla released Firefox Home, a companion app for the iPhone and iPod Touch based on theFirefox Synctechnology, which allowed users to access their Firefox browsing history, bookmarks, and recent tabs. It also included Firefox's "Awesomebar" location bar. Firefox Home was not a web browser, the application launched web pages in either an embedded viewer for that one page, or by opening the page in the Safari app.Mozilla pulled Firefox Home from theApp Storein September 2012, stating it would focus its resources on other projects. The company subsequently released thesource codeof Firefox Home's underlying synchronization software.

In April 2013, then-Mozilla CEOGary Kovacssaid that Firefox would not come to iOS if Apple required the use of theWebKitlayout engine to do so. One reason given by Mozilla was that prior to iOS 8, Apple had supplied third-party browsers with an inferior version of their JavaScript engine which hobbled their performance, making it impossible to match Safari's JavaScript performance on the iOS platform.Apple later opened their "Nitro" JavaScript engine to third-party browsers.In 2015, Mozilla announced it was moving forward with Firefox for iOS, with a preview release made available in New Zealand in September of that year.It was fully released in November later that year.It is the first Firefox-branded browser not to use theGeckolayout engineas is used in Firefox fordesktopandmobile.Apple's policies require all iOS apps that browse the web to use the built-inWebKitrendering framework and WebKit JavaScript, so using Gecko is not possible.UnlikeFirefox on Android,Firefox for iOS does not support browser add-ons.

In November 2016, Firefox released a new iOS app titledFirefox Focus,a private web browser.

Firefox Reality (AR/VR)

Firefox Reality was released for Augmented Reality and Virtual Reality headsets in September 2018.It supports traditional web-browsing through 2D windows and immersive VR pages throughWeb VR.Firefox Reality is available onHTC Vive,Oculus,Google DaydreamandMicrosoft Hololensheadsets. In February 2022 Mozilla announced thatIgaliatook over stewardship of this project under the new name of Wolvic.

Unofficial ports

Firefox has also been ported toFreeBSD,NetBSD,OpenBSD,OpenIndiana,OS/2,ArcaOS,SkyOS,RISC OSandBeOS/Haiku,and an unofficial rebranded version calledTimberwolfhas been available forAmigaOS 4.An unofficial continuation of the Mac OS XPowerPCrelease was actively developed asTenFourFoxuntil October 5, 2021.

The Firefox port for OpenBSD is maintained by Landry Breuil since 2010. Firefox is regularly built for the current branch of the operating system, the latest versions are packaged for each release and remain frozen until the next release. In 2017, Landry began hosting packages of newer Firefox versions for OpenBSD releases from 6.0 onwards, making them available to installations without the ports system.

TheSolarisport of Firefox (includingOpenSolaris) was maintained by the Oracle Solaris Desktop Beijing Team,until March 2017 when the team was disbanded.There was also an unofficial port ofFirefox 3.6.x toIBM AIXand of v1.7.x toUnixWare.

Operating system			Latest stable version	Support status
Solaris	11		Older version, yet still maintained:115.12.0esr (x64, SPARC V9)	2011–
	10 and OpenSolaris		Old version, no longer maintained:52.9.0esr (IA-32, x64, SPARC V9)	2005–2018
	8–9		Old version, no longer maintained:2.0.0.20 (IA-32 and SPARC V9)	2004–2008
AIX	7.1 and 7.2		Old version, no longer maintained:3.6.25 (POWER)	N/A
HP-UX	11i v2–v3		Old version, no longer maintained:3.5.9 (IA-64, PA-RISC)	N/A
FreeBSD(Tier 1)	13 and later		Current stable version:128.0 (x64, ARM64)	2021–
			Older version, yet still maintained:115.13.0esr (x64, ARM64)
	12		Old version, no longer maintained:121.0 (IA-32)	2018–2024
			Old version, no longer maintained:115.6.0esr (IA-32)
OpenBSD	-stable	7.5	Current stable version:128.0 (x64, ARM64, RISC-V)	2024–
			Older version, yet still maintained:115.13.0esr (x64, ARM64)
		6.9	Old version, no longer maintained:88.0.1 (IA-32)	2021
			Old version, no longer maintained:78.14.0esr (IA-32)
		5.8	Old version, no longer maintained:38.7.1esr (PPC)	2015–2016
		5.7	Old version, no longer maintained:31.6.0esr (SPARC V9)	2015
	-release	5.8	Old version, no longer maintained:39.0.3 (PPC)	N/A
		5.4	Old version, no longer maintained:3.6.28 (Alpha)
		4.7	Old version, no longer maintained:3.0.18 (ARM)

Legend:

Old version

Older version, still maintained

Latest version

Latest preview version

Future release

Channels and release schedule

In March 2011, Mozilla presented plans to switch to therapid release model,a faster 16-weekdevelopment cycle,similar toGoogle Chrome.Ars Technicanoted that this new cycle entailed "significant technical and operational challenges" for Mozilla (notably preserving third-partyadd-oncompatibility), but that it would help accelerate Firefox's adoption of new web standards, feature, and performance improvements.This plan was implemented in April 2011.The release process was split into four "channels", with major releases trickling down to the next channel every six to eight weeks. For example, the Nightly channel would feature a preliminary unstable version of Firefox 6, which would move to the experimental "Aurora" channel after preliminary testing, then to the more stable "beta" channel, before finally reaching the public release channel, with each stage taking around six weeks.For corporations, Mozilla introduced an Extended Support Release (ESR) channel, with new versions released every 30 weeks (and supported for 12 more weeks after a new ESR version is released), though Mozilla warned that it would be less secure than the release channel, since security patches would only bebackportedfor high-impact vulnerabilities.

In 2017, Mozilla abandoned the Aurora channel, which saw low uptake, andrebasedFirefox Developer Edition onto the beta channel.Mozilla usesA/B testingand a staged rollout mechanism for the release channel, where updates are first presented to a small fraction of users, with Mozilla monitoring its telemetry for increased crashes or other issues before the update is made available to all users.In 2020, Firefox moved to a four-week release cycle, to catch up with Chrome in support for new web features.Chrome switched to a four-week cycle a year later.

Licensing

Firefoxsource codeisfree software,with most of it being released under theMozilla Public License(MPL) version 2.0.This license permits anyone to view, modify, or redistribute the source code. As a result, several publicly released applications have been built from it, including Firefox's predecessorNetscapeas well as the privacy focussedTor Browser.

In the past, Firefox was licensed solely under the MPL, then version 1.1,which theFree Software Foundationcriticized for beingweak copyleft,as the license permitted, in limited ways, proprietaryderivative works.Additionally, code only licensed under MPL 1.1 could not legally be linked with code under theGPL.To address these concerns, Mozilla re-licensed most of Firefox under thetri-licensescheme of MPL 1.1, GPL 2.0, orLGPL2.1. Since the re-licensing, developers were free to choose the license under which they received most of the code, to suit their intended use: GPL or LGPL linking and derivative works when one of those licenses is chosen, or MPL use (including the possibility of proprietary derivative works) if they chose the MPL.However, on January 3, 2012, Mozilla released the GPL-compatible MPL 2.0,and with the release of Firefox 13 on June 5, 2012, Mozilla used it to replace the tri-licensing scheme.

Trademark and logo

See also:Mozilla software rebranded by Debian

The name "Mozilla Firefox" is aregistered trademarkof Mozilla; along with the official Firefox logo, it may only be used under certain terms and conditions. Anyone may redistribute the official binaries in unmodified form and use the Firefox name and branding for such distribution, but restrictions are placed on distributions which modify the underlying source code.The name "Firefox" derives from a nickname of thered panda.

Mozilla has placed the Firefox logo files under open-source licenses,but its trademark guidelines do not allow displaying alteredor similar logosin contexts where trademark law applies.

Logo used forIceweasel

There has been some controversy over the Mozilla Foundation's intentions in stopping certain open-source distributions from using the "Firefox" trademark.Open-source browsers "enable greater choice and innovation in the market rather than aiming for mass-market domination."Mozilla Foundation ChairpersonMitchell Bakerexplained in an interview in 2007 that distributions could freely use the Firefox trademark if they did not modify source code, and that the Mozilla Foundation's only concern was with users getting a consistent experience when they used "Firefox".

To allow distributions of the codewithoutusing the official branding, the Firefoxbuild systemcontains a "branding switch". This switch, often used for Alpha s ( "Auroras" ) of future Firefox versions, allows the code to be compiled without the official logo and name and can allow a derivative work unencumbered by restrictions on the Firefox trademark to be produced. In the unbranded build, the trademarked logo and name are replaced with a freely distributable generic globe logo and the name of the release series from which the modified version was derived.

Distributing modified versions of Firefox under the "Firefox" name required explicit approval from Mozilla for the changes made to the underlying code, and required the use ofallof the official branding. For example, it was not permissible to use the name "Firefox" without also using the official logo. When theDebianproject decided to stop using the official Firefox logo in 2006 (because Mozilla's copyright restrictions at the time were incompatible withDebian's guidelines), they were told by a representative of the Mozilla Foundation that this was not acceptable and was asked either to comply with the published trademark guidelines or cease using the "Firefox" name in their distribution.Debian switched to branding their modified version of Firefox "Iceweasel"(but in 2016 switched back to Firefox), along with other Mozilla software.GNU IceCatis another derived version of Firefox distributed by theGNU Project,which maintains its separate branding.

Branding and visual identity

Main article:Firefox logo

The Firefox icon is a trademark used to designate the official Mozilla build of the Firefox software and builds of official distribution partners.For this reason, software distributors who distribute modified versions of Firefox do not use the icon.

Early Firebird and Phoenix releases of Firefox were considered to have reasonable visual designs but fell short when compared to many other professional software packages. In October 2003, professional interface designer Steven Garrity authored an article covering everything he considered to be wrong with Mozilla's visual identity.

Shortly afterwards, the Mozilla Foundation invited Garrity to head up the new visual identity team. The release of Firefox 0.8 in February 2004 saw the introduction of the new branding efforts. Included were new icon designs by silverorange, a group of web developers with a long-standing relationship with Mozilla. The final renderings are byJon Hicks,who had worked onCamino.The logo was later revised and updated, fi xing several flaws found when it was enlarged.The animal shown in the logo is a stylized fox, although "firefox" is usually a common name for thered panda.The panda, according to Hicks, "didn't really conjure up the right imagery" and was not widely known.

In June 2019, Mozilla unveiled a revised Firefox logo, which was officially implemented on version 70. The new logo is part of an effort to build a brand system around Firefox and its complementary apps and services, which are now being promoted as a suite under the Firefox brand.

• Logo history
• 
  Logo of "Phoenix" and "Firebird" before being renamed as Firefox
• 
  Firefox 0.8–0.10, from February 9, 2004, to November 8, 2004
• 
  Firefox 1.0–3.0, from November 9, 2004, to June 29, 2009
• 
  Firefox 3.5–22, from
  June 30, 2009, to
  August 5, 2013
• 
  Firefox 23–56, from August 6, 2013, to November 13, 2017
• 
  Firefox 57–69, from November 14, 2017, to October 21, 2019
• 
  Firefox 70 or later, since October 22, 2019

• Other logos, used for nightly versions
• 
  The 2011 Nightly logo, used to representnightly buildsofpre- Alpha versions
• 
  The 2013 Nightly logo
• 
  The 2017 Nightly logo
• 
  The 2019 Nightly logo

• Other logos, used for developer/aurora versions
• 
  The 2011 Aurora logo, used to represent anAlpha release
• 
  The 2013 Aurora logo
• 
  The 2015 Developer Edition logo
• 
  The 2017 Developer Edition logo
• 
  The 2019 Developer Edition logo

• Other logos
• 
  Blue globe artwork, distributed with thesource code,and is explicitly not protected as a trademark
• 
  The logo for the Firefox brand of products and services, as of July 2019. It appears as if the fox was removed, but this is not the logo for the browser itself.

Promotion

Firefox mascot at theFISL16 (2015), Brazil

Firefox was adopted rapidly, with 100 million downloads in its first year of availability.This was followed by a series of aggressive marketing campaigns starting in 2004 with a series of eventsBlake Rossand Asa Dotzler called "marketing weeks".

Firefox continued to heavily market itself by releasing a marketing portal dubbed "Spread Firefox" (SFX) on September 12, 2004.It debuted along with the Firefox Preview Release, creating a centralized space for the discussion of various marketing techniques. The release of theirmanifestostated that "the Mozilla project is a global community of people who believe that openness, innovation and opportunity are key to the continued health of the Internet."A two-page ad in the edition of December 16 ofThe New York Times,placed by Mozilla Foundation in coordination with Spread Firefox, featured the names of the thousands of people worldwide who contributed to the Mozilla Foundation's fundraising campaign to support the launch of the Firefox 1.0 web browser.SFX portal enhanced the "Get Firefox" button program, giving users "referrer points" as an incentive. The site lists the top 250 referrers. From time to time, the SFX team or SFX members launch marketing events organized at the Spread Firefox website. As a part of the Spread Firefox campaign, there was an attempt to break the world download record with the release of Firefox 3.This resulted in an official certifiedGuinness world record,with over eight million downloads.In February 2011, Mozilla announced that it would be retiring Spread Firefox (SFX). Three months later, in May 2011, Mozilla officially closed Spread Firefox. Mozilla wrote that "there are currently plans to create a new iteration of this website [Spread Firefox] at a later date."

In celebration of the third anniversary of the founding of theMozilla Foundation,the "World Firefox Day" campaign was established on July 15, 2006,and ran until September 15, 2006.Participants registered themselves and a friend on the website for nomination to have their names displayed on the Firefox Friends Wall, a digital wall that was displayed at the headquarters of the Mozilla Foundation.

The Firefox community has also engaged in the promotion of their web browser. In 2006, some of Firefox's contributors fromOregon State Universitymade acrop circleof the Firefox logo in anoatfield nearAmity, Oregon,near the intersection of Lafayette Highway and Walnut Hill Road.After Firefox reached 500 million downloads on February 21, 2008, the Firefox community celebrated by visitingFreericeto earn 500 million grains of rice.

Other initiatives included Live Chat – a service Mozilla launched in 2007 that allowed users to seek technical support from volunteers.The service was later retired.

To promote the launch of Firefox Quantum in November 2017, Mozilla partnered withReggie Wattsto produce a series of TV ads and social media content.

Performance

2000s

In December 2005,Internet Weekran an article in which many readers reported high memory usage in Firefox 1.5.Mozilla developers said that the higher memory use of Firefox 1.5 was at least partially due to the new fast backwards-and-forwards (FastBack) feature.Other known causes of memory problems were malfunctioning extensions such asGoogle Toolbarand some older versions ofAdBlock,or plug-ins, such as older versions of Adobe Acrobat Reader.WhenPC Magazinein 2006 compared memory usage of Firefox 2,Opera 9,andInternet Explorer 7,they found that Firefox used approximately as much memory as each of the other two browsers.

In 2006,Softpedianoted that Firefox 1.5 took longer to start up than other browsers,which was confirmed by furtherspeed tests.

Internet Explorer 6 launched more swiftly than Firefox 1.5 onWindows XPsince many of its components were built into the OS and loaded during system startup. As a workaround for the issue, a preloader application was created that loaded components of Firefox on startup, similar to Internet Explorer.AWindows Vistafeature calledSuperFetchperforms a similar task of preloading Firefox if it is used often enough.

Tests performed byPC Worldand Zimbra in 2006 indicated that Firefox 2 used less memory than Internet Explorer 7.Firefox 3 used less memory than Internet Explorer 7, Opera 9.50 Beta,Safari3.1 Beta, and Firefox 2 in tests performed by Mozilla, CyberNet, and The Browser World.In mid-2009, BetaNews benchmarked Firefox 3.5 and declared that it performed "nearly ten times better on XP than Microsoft Internet Explorer 7".

2010s

In January 2010, Lifehacker compared the performance of Firefox 3.5, Firefox 3.6, Google Chrome 4 (stable and Dev versions), Safari 4, and Opera (10.1 stable and 10.5 pre- Alpha versions). Lifehacker timed how long browsers took to start and reach a page (both right after boot-up and after running at least once already), timed how long browsers took to load nine tabs at once, tested JavaScript speeds using Mozilla's Dromaeo online suite (which implements Apple'sSunSpiderand Google's V8 tests) and measured memory usage using Windows 7's process manager. They concluded that Firefox 3.5 and 3.6 were the fifth- and sixth-fastest browsers, respectively, on startup, 3.5 was third- and 3.6 was sixth-fastest to load nine tabs at once, 3.5 was sixth- and 3.6 was fifth-fastest on the JavaScript tests. They also concluded that Firefox 3.6 was the most efficient with memory usage followed by Firefox 3.5.

In February 2012,Tom's Hardwareperformance tested Chrome 17, Firefox 10,Internet Explorer 9,Opera 11.61, and Safari 5.1.2 on Windows 7.Tom's Hardwaresummarized their tests into four categories: Performance, Efficiency, Reliability, and Conformance. In the performance category they testedHTML5,Java,JavaScript,DOM,CSS 3,Flash,Silverlight,andWebGL(WebGL 2is current as of version 51; and Java and Silverlight stop working as of version 52)—they also tested startup time and page load time. The performance tests showed that Firefox was either "acceptable" or "strong" in most categories, winning three categories (HTML5, HTML5hardware acceleration,and Java) only finishing "weak" in CSS performance. In the efficiency tests,Tom's Hardwaretested memory usage and management. In this category, it determined that Firefox was only "acceptable" at performing light memory usage, while it was "strong" at performing heavy memory usage. In the reliability category, Firefox performed a "strong" amount of proper page loads. In the final category, conformance, it was determined that Firefox had "strong" conformance for JavaScript and HTML5. In conclusion,Tom's Hardwaredetermined that Firefox was the best browser for Windows 7 OS, but that it only narrowly beat Google Chrome.

In June 2013,Tom's Hardwareagain performance tested Firefox 22, Chrome 27, Opera 12, andInternet Explorer 10.They found that Firefox slightly edged out the other browsers in their "performance" index, which examined wait times, JavaScript execution speed, HTML5/CSS3 rendering, and hardware acceleration performance. Firefox also scored the highest on the "non-performance" index, which measured memory efficiency, reliability, security, and standards conformance, finishing ahead of Chrome, the runner-up.Tom's Hardwareconcluded by declaring Firefox the "sound" winner of the performance benchmarks.

In January 2014, a benchmark testing the memory usage of Firefox 29, Google Chrome 34, andInternet Explorer 11indicated that Firefox used the least memory when a substantial number of tabs were open.

In benchmark testing in early 2015 on a "high-end" Windows machine, comparingMicrosoft Edge,Internet Explorer, Firefox, Chrome, and Opera, Firefox achieved the highest score on three of the seven tests. Four different JavaScript performance tests gave conflicting results. Firefox surpassed all other browsers on thePeacekeeper benchmarkbut was behind the Microsoft products when tested with SunSpider. Measured with Mozilla's Kraken, it came second place to Chrome, while on Google'sOctanechallenge it took third behind Chrome and Opera. Firefox took the lead with WebXPRT, which runs several typical HTML5 and JavaScript tasks. Firefox, Chrome, and Opera all achieved the highest possible score on the Oort Online test, measuring WebGL rendering speed (WebGL 2 is now current). In terms of HTML5 compatibility testing, Firefox was ranked in the middle of the group.

A similar set of benchmark tests in 2016 showed Firefox's JavaScript performance on Kraken and the newerJetstreamtests trailing slightly behind all other tested browsers except Internet Explorer (IE), which performed relatively poorly. On Octane, Firefox came ahead of IE and Safari, but again slightly behind the rest, includingVivaldiand Microsoft Edge. Edge took overall first place on the Jetstream and Octane benchmarks.

Firefox Quantum

As of the adoption of Firefox 57 and Mozilla'sQuantum projectentering production browsers in November 2017, Firefox was tested to be faster than Chrome in independent JavaScript tests, and demonstrated to use less memory with many browser tabs opened.TechRadarrated it as the fastest web browser in a May 2019 report.

Usage share

Further information:Usage share of web browsers

Usage share of web browsersaccording toStatCounter

Downloads have continued at an increasing rate since Firefox 1.0 was released on November 9, 2004, and as of 31 July 2009Firefox had already been downloaded over one billion times.This number does not include downloads using software updates or those from third-party websites.They do not represent a user count, as one download may be installed on many machines, one person may download the software multiple times, or the software may be obtained from a third-party.

In July 2010,IBMasked all employees (about 400,000) to use Firefox as their default browser.

Firefox was the second-most used web browser until November 2011, when Google Chrome surpassed it.According to Mozilla, Firefox had more than 450 million users as of October 2012.

In January 2024, Firefox was the fourth-most widely used desktop browser, and it was the fourth-most popular with 3.3% of worldwideusage share of web browsersacross all platforms.

Desktop/laptop browser statistics Google Chrome   64.84% Microsoft Edge   12.96% Safari   8.83% Mozilla Firefox   7.57% Opera   3.23% Other   2.57% Desktop web browser market share according toStatCounterfor January 2024

According to the Firefox Public Data report by Mozilla, the active monthly count of Desktop clients has decreased from around 310 million in 2017 to 200 million in 2023. From Oct 2020, the desktop market share of Firefox started to decline in countries where it used to be the most popular. In Eritrea, it dropped from 50% in Oct 2020 to 9.32% in Sept 2021. In Cuba, it dropped from 54.36% in Sept 2020 to 38.42% in Sept 2021.

The UKand USgovernments both follow the 2% rule. This states that only browsers with more than 2% market share among visitors of their websites will be supported. There are concerns that support for Firefox will be dropped because as of December 29, 2023, the browser market share among US government website visitors is 2.2%.

See also

• Firefox User Extension Library
• History of the web browser
• List of free and open-source software packages
• Mozilla Prism
• XULRunner

Further reading

• Cheah, Chu Yeow (2005).Firefox Secrets: A Need-to-Know Guide.O'Reilly.ISBN978-0-9752402-4-3.
• Feldt, Kenneth C. (2007).Programming Firefox.O'Reilly.ISBN978-0-596-10243-2.
• Granneman, Scott (2005).Don't Click on the Blue e!: Switching to Firefox.O'Reilly.ISBN978-0-596-00939-7.
• Hofmann, Chris; Marcia Knous; John Hedtke (2005).Firefox and Thunderbird Garage.Prentice Hall PTR.ISBN978-0-13-187004-8.
• McFarlane, Nigel (2005).Firefox Hacks.O'Reilly.ISBN978-0-596-00928-1.
• Reyes, Mel (2005).Hacking Firefox: More Than 150 Hacks, Mods, and Customizations.Wiley.ISBN978-0-7645-9650-6.
• Ross, Blake(2006).Firefox for Dummies.Wiley.ISBN978-0-471-74899-1.

External links

• Official website
• FirefoxatCurlie
• FirefoxatMicrosoft Store