Version
Release date
Gecko
Release notes
0.1
2002-09-23
1.2
0.2
2002-10-01
Web form auto-complete
Sidebar is back
Downloads Sidebar
Bookmarks Sidebar
History Sidebar
Extension management
Toolbar customization
Search bar
Improved preference defaults
Speed improvements
Ctrl+Mousewheel to resize fonts
Bug fixes
0.3
2002-10-14
Image Blocking
Pop-up Blocking Whitelist
Bookmarks Changes
Global Go Menu and Other Menu Changes
Tabbed Browsing Improvements
Size and Speed Improvements
Bug fixes
0.4
2002-10-19
1.3
Improvements to pop-up blocking
Improvements to toolbar customization
Improvements to tabbed browsing and shortcut keys
Type ahead find returns
Address bar gets smarter
Themes
Bug fixes
0.5
2002-12-07
Multiple homepages
Intellimouse 5-button support
Sidebar remembers its state across sessions
Download fixes
History improvements
Accessibility improvements
Size and memory reduction
Performance improvements
Stability improvements
Better Windows appearance
Many more new themes
Many bug fixes
0.6
2003-05-17
1.5
New default theme
Redesigned Preferences window
Improved Privacy Options
Improved Bookmarks
Talkback enabled to tell Mozilla why the browser crashed
Automatic Image Resizing
Smooth Scrolling
Access to more preferences through about:config
Custom profile save location
Mac OS X compatibility
Lots of bug fixes
0.7
2003-10-15
Advanced preferences panel
Download/helper apps preferences panel
Cookie whitelisting
New password manager (all passwords now stored encrypted)
Web panels (like Mozilla's sidebar panels)
Alternate stylesheet support (through a status bar button)
Send Page, Send Link, and Send Image menu items
Autoscroll
Lots of bug fixes and other small improvements
0.8
2004-02-09
1.6
Windows Installer
Download Manager
New Add Bookmark Dialog
Work Offline
Better Handling of File Types
New XPInstall Frontend
New default theme for Mac OS X
Lots of bug fixes and improvements
0.9
2004-05-15
1.7
New Default Theme
Comprehensive Data Migration from Internet Explorer
Extension/Theme Manager
Smaller Download
Online help system
Lots of bug fixes and improvements
1.0
2004-11-09
Better Tabbed Browsing Controls
Horde of bug fixes
1.0.8
2006-04-13
Security fixes
Bug fixes
Stability fixes
1.5
2005-11-29
1.8
Dropped support for Mac OS X v10.1, minimum is now Mac OS X v10.2
Private data clear data
Back and forward now fast
Improved web standards
Improved HTML
Improved CSS
Improved HTTP
Improved JavaScript/DOM
SVG compatibility
Huge amount of bug fixes
1.5.0.12
2007-05-30
Bug fixes
Stability fixes
Security fixes
2.0
2006-10-24
1.8.1
Visual Refresh of main theme
Built-in phishing protection
Enhanced search capabilities
Improved tabbed browsing
Resuming your browsing session (session restore)
Previewing and subscribing to Web feeds
Inline spell checking
Live Web Titles
Improved Add-ons manager
JavaScript 1.7
Extended search plugin format (predictive search)
Improved security with extension system
Client-side session and persistent storage
SVG text support
New Windows installer
2.0.0.20
2008-12-18
Bug fixes
Security fixes
Stability fixes
3.0
2008-06-17
1.9
One-click site info
Malware Protection
New Web Forgery Protection page
New SSL error pages
Add-ons and Plugin version check
Secure add-on updates
Anti-virus integration with download manager
Vista Parental Controls
Effective top-level domain (eTLD) service better restricts cookies and other restricted content to a single domain.
Better protection against cross-site JSON data leaks.
Easier password management – save passwords after successful login
Simplified add-on installation from 3rd party’s
New Download Manager
Resumable downloading after closing the browser
Full page zoom
Podcasts and Videocasts can be associated with your media playback tools
Tab scrolling and quickmenu
Save what you were doing - Firefox 3 will prompt users to save tabs on exit.
Optimized Open in Tabs behavior
Location and Search bar size can now be customized with a simple resizer item.
Text selection improvements (select multiple selections of text)
Find toolbar: the Find toolbar now opens with the current selection.
Plugin management with the add-on manager
Improved integration with Windows
Improved integration with the Mac
Integration with Linux GTK theme
Bookmark star button
Bookmark tags
Smart Location Bar
Library of bookmarks, history, etc.
Smart Bookmark Folders
Web-based protocol handlers for mail:to
Download & Install Add-ons from the Add-on manager
Easy to use Download Actions
New graphics and font handling in Gecko 1.9 provide rendering improvements in:
CSS
SVG
Display of fonts with ligatures and complex scripts
Color management of images with capabilities
Offline support for web applications
Improved speed
Reduced memory usage
Increased reliability
25000 total code changes
Security fixes
Stability fixes
3.0.19
2010-03-30
Fixed several security problems.
Fixed several stability issues.
3.5
2009-06-30
1.9.1
Support for the HTML5 and elements including native support for Ogg Theora video and Vorbis audio
Improved tools for controlling your private data, including a Private Browsing Mode
Better web application performance using the new TraceMonkey JavaScript engine
The ability to share your location with websites using Location Aware Browsing
Support for native JSON, and web worker threads
Improvements to the Gecko layout engine, including speculative parsing for faster content rendering
Support for new web technologies such as:
Downloadable fonts
CSS media queries
New transformations and properties
JavaScript query selectors
HTML5 local storage and offline application storage
text ICC profiles
SVG transforms.
3.5.19
2011-04-28
Fixed several security issues
Fixed several stability issues
3.6
2010-01-21
1.9.2
Support for Persona themes
Protection from out-of-date plugins to keep users safer as they browse.
Open, native video can now be displayed full screen and supports poster frames.
Improved JavaScript performance, overall browser responsiveness, and startup time.
The ability for web developers to indicate that scripts should run asynchronously to speed up page load times.
Continued support for downloadable web fonts using the new WOFF font format.
Support for new CSS attributes such as gradients, background sizing, and pointer events.
Support for new DOM and HTML5 specifications including the Drag & Drop API and the File API, which allow for more interactive web pages.
Changes to how third-party software can integrate with Firefox in order to prevent crashes.
3.6.28
2012-03-13
Added Out-of-process plugins
Fixed several security issues
Fixed several stability issues
4.0
2011-03-22
2.0
Firefox 4 is available in over 80 languages
Uses JägerMonkey, a faster JavaScript engine
Support for Do Not Track ("DNT") header that allows users to opt-out of behavioral advertising
Firefox Sync is included by default
Graphic rendering is now hardware-accelerated using Direct3D 9 (Windows XP), Direct3D 10 (Windows Vista & 7), and OpenGL on Mac OS
Direct2D Hardware Acceleration is now on by default for Windows 7 users
WebGL is enabled on all platforms that have a capable graphics card with updated drivers
Native support for the HD HTML5 WebM video format, hardware accelerated where available
Firefox button has a new look for Windows Vista and Windows 7 users
Tabs are now on top by default on Windows, Mac OS X, and Linux
You can search for and switch to already open tabs in the Smart Location Bar
The stop and reload buttons have been merged into a single button on Windows, Mac OS X, and Linux
The Bookmarks Toolbar has been replaced with a Bookmarks Button by default (you can switch it back if you'd like)
Crash protection when there is a crash in Adobe Flash Player, Apple QuickTime or Microsoft Silverlight plugins
You can turn any tab into an "App Tab"
The default homepage design has been refreshed
Overhaul of the bookmarks and history code, enabling faster bookmarking and startup performance
Per-compartment garbage collection is now enabled, reducing work done during complex animations
Additional polish for the Firefox add-on Manager
Improved web typography using OpenType with support for ligatures, kerning and font variants
Web developers can animate content using CSS Transitions
Responsiveness and scrolling improvements from the new retained layers layout system
HTML5 Forms API makes web based forms easier to implement and validate
Support for the new proposed Audio Data API
Support for HSTS security protocol allowing sites to insist that they only be loaded over SSL
A new feature called Panorama gives users a visual overview of all open tabs, allowing them to be sorted and grouped
An experimental API is included to provide more efficient Javascript animations
Firefox now supports the HTML5 video "buffered" property
Changes to how XPCOM components are registered in order to help startup time and process separation
New Addons Manager and extension management API
Significant API improvements are available for JS-ctypes, a foreign function interface for extensions
CSS Transitions are partially supported
Core Animation rendering model for plugins on Mac OS X
Web developers can update the URL field without reloading the page using HTML History APIs
More responsive page rendering using lazy frame construction
Link history lookup is done asynchronously to provide better responsiveness during pageload
CSS :visited selectors have been changed to block websites from being able to check a user's browsing history
New HTML5 parser
Support for more HTML5 form controls
Web authors can now get touch events from Firefox users on Windows 7 machines
A new way of representing values in JavaScript that allows Firefox to execute heavy, numeric code more efficiently
4.0.1
2011-04-28
Fixed several security issues
Fixed several stability issues
5.0
2011-06-21
5.0
Better standards support for HTML5, CSS3, MathML, XHR and SMIL
Better visibility for the Do not track header preference
Stability and security improvements
Better tuned HTTP idle connection logic
Improved canvas, JavaScript, memory, and networking performance
Improved spell checking for some locales
Improved desktop environment integration for Linux users
Better WebGL security (WebGL content can no longer load cross-domain textures).
Background tabs have setTimeout and setInterval clamped to 1000 ms to improve performance
5.0.1
2011-07-11
Fixed an issue in Mac OS X 10.7 that could cause Firefox to crash
Fixed an issue caused by Apple's "Java for Mac OS X 10.6 Update 5" where the Java plugin would not be loaded
6.0
2011-08-16
6.0
about:permissions, a permissions manager. The user can choose what information can be shared with sites, e.g. location.
The address bar now highlights the domain of the website you are visiting.
Streamlined the look of the site identity block
Added support for the latest draft version of WebSockets with a prefixed API
Added support for EventSource / server-sent events
Added support for window.matchMedia
Added Scratchpad, an interactive JavaScript prototyping environment
Added a new Web Developer menu item and moved development-related items into it
Improved usability of the Web Console
Improved the discoverability of Firefox Sync
Reduced browser startup time when using Panorama
Fixed several stability issues
Fixed several security issues
6.0.2
2011-09-06
Revoked the root certificate for DigiNotar due to fraudulent SSL certificate issuance
Removed trust exceptions for certificates issued by Staat der Nederlanden
Resolved an issue with gov.uk websites
7.0
2011-09-27
7.0
Drastically improved memory handling for certain use cases
Added a new rendering backend to speed up Canvas operations on Windows systems
Bookmark and password changes now sync almost instantly when using Firefox Sync
The 'http://' URL prefix is now hidden by default.
Added support for text-overflow: ellipsis
Added support for the Web Timing specification
Enhanced support for MathML
The WebSocket protocol has been updated from version 7 to version 8.
Added an opt-in system for users to send performance data back to Mozilla to improve future versions of Firefox
Fixed several stability issues
Fixed several security issues
7.0.1
2011-09-29
Fixed a rare issue where some users could find one or more of their add-ons hidden after a Firefox update
8.0
2011-11-08
8.0
Add-ons installed by third-party programs are now disabled by default
Added a one-time add-on selection dialog to manage previously installed add-ons
Added Twitter to the search bar
Added a preference to load tabs on demand, improving start-up time when windows are restored
Improved performance and memory handling when using and elements
Added Cross-Origin Resource Sharing (CORS) support for cross-domain textures in WebGL
Added support for HTML5 context menus
Added support for insertAdjacentHTML
Improved CSS hyphen support for many languages
Improved WebSocket support
Fixed several stability issues
8.0.1
2011-11-21
Fixed Mac OS X crash that occurred in certain instances when a Java Applet is loaded with Java SE 6 version 1.6.0_29 installed.
Fixed Windows startup crash caused by RoboForm versions older than 7.6.2.
9.0
2011-12-20
9.0
Added type inference, significantly improving JavaScript performance.
Improved theme integration for Mac OS X Lion.
Added two finger swipe navigation for Mac OS X Lion.
Added support for querying Do Not Track status via JavaScript.
Added support for the font-stretch CSS property.
Improved support for the text-overflow CSS property.
Improved standards support for HTML5, MathML, and CSS.
Fixed several stability issues.
9.0.1
2011-12-21
Fixed crash on Windows, Mac and Linux
10.0
2012-01-31
10.0
Most add-ons are now compatible with new versions of Firefox by default.
Anti-Aliasing for WebGL is now implemented.
CSS3 3D-Transforms are now supported.
New element for bi-directional text isolation, along with supporting CSS properties.
Full Screen APIs allow you to build a web application that runs full screen.
10.0.1
2012-02-10
10.0.2
2012-02-16
Fixed Java applets that sometimes caused text input to become unresponsive.
10.0.3esr
2012-03-13
Security fixes.
Fixed web workers running out of memory, affecting some add-ons used by organizations.
10.0.4esr
2012-04-24
Fixed an issue in Firefox ESR 10.0.3 that caused the "Whats New" page to open after an update.
Fixed extensions.checkCompatibility.* prefs not working in ESR releases.
10.0.5esr
2012-06-05
Fixed the 10.0.5 Firefox top crash with signature .
10.0.6esr
2012-07-17
Security fixes.
Stability fixes.
Fixed some text editing inconsistencies.
10.0.7esr
2012-08-28
Fixed contenteditable breaks in 10.0.7 that middle-click to open links
Addressed a fix that allows specifying wildcard that matches all simple netbiosnames in network.automatic-ntlm-auth.trusted-uris.
10.0.8esr
2012-10-09
10.0.9esr
2012-10-12
10.0.10esr
2012-10-26
10.0.11esr
2012-11-20
11.0
2012-03-13
11.0
Migration of settings from Google Chrome
SPDY protocol support (disabled by default)
RFC 6455 WebSocket protocol support with a unprefixed API
Page Inspector Tilt (3D View)
Sync Add-ons
Redesigned HTML5 video controls
Style Editor (CSS)
12.0
2012-04-24
12.0
Windows: Firefox is now easier to update with one less prompt (User Account Control)
Reintroduced on-demand loading of pinned tabs after restoring a session
Page Source now has line numbers
Line breaks are now supported in the title attribute
Improvements to "Find in Page" to center search result
URLs pasted into the download manager window are now automatically downloaded
Support for the text-align-last CSS property has been added
Experimental support for ECMAScript 6 Map and Set objects has been implemented
Various security fixes
Many bug fixes
Some TinyMCE-based editors failed to load (739141)
OS X: WebGL performance may be degraded on some hardware (713305)
13.0
2012-06-05
13.0
When opening a new tab, users are now presented with their most visited pages
The default home page now has quicker access to bookmarks, history, settings, and more
SPDY protocol now enabled by default for faster browsing on supported sites
Restored background tabs are not loaded by default for faster startup
Smooth scrolling is now enabled by default
72 total improvements to Page Inspector, HTML panel, Style Inspector, Scratchpad and Style Editor
The column-fill CSS property has been implemented
Experimental support for ECMAScript 6 Map and Set objects has been implemented
Support for the CSS3 background-position property extended syntax has been added
The :invalid pseudo-class can now be applied to the element
The CSS turn angle unit is now supported
13.0.1
2012-06-15
Fixed an issue when Windows Messenger did not load in Hotmail, and the Hotmail inbox did not auto-update
Fixed the Hebrew text that was sometimes rendered incorrectly
Fixed an issue in Adobe Flash 11.3 that sometimes caused a crash on quit
Various security fixes
14.0
2012-06-26
14.0
Google searches now utilize HTTPS
Full screen support for Mac OS X Lion implemented
Plugins can now be configured to only load on click (about:config)
The Awesome Bar now auto-completes typed URLs
Improved site identity manager, to prevent spoofing of an SSL connection with favicons
Pointer Lock API implemented
New API to prevent your display from sleeping
New text-transform and font-variant CSS improvements for Turkic languages and Greek
Long URLs now extend the status bar almost to the whole width of the viewport.
Gstreamer backend for HTML5 video to allow H.264 playback (needs to be enabled at compile time).
14.0.1
2012-07-17
Various security fixes
Fixed the GIF animation that can get stuck when src and image size are changed
Mac OSX: Fixed the nsCocoaWindow::ConstrainPosition that uses wrong screen in multi-display setup
Fixed the CSS :hover regression when an element's class name is set by Javascript
15.0
2012-08-28
15.0
Silent update: Background updates
Support for SPDY networking protocol v3
WebGL enhancements, including compressed textures for better performance
Localization in Maithili
Optimized memory usage for add-ons
JavaScript debugger integrated into developer tools
New layout view added to Inspector
High precision event timer implemented
The CSS word-break property has been implemented
New responsive design tool allows web developers to switch between desktop and mobile views of sites
Native support for the Opus audio format added
The and elements now support the played attribute
The source element now supports the media attribute
Fixed the focus rings that keep growing when repeatedly tabbing through elements
15.0.1
2012-09-06
Addressed a fix where sites visited while in Private Browsing mode could be found through manual browser cache inspection
16.0
2012-10-09
16.0
Firefox on Mac OS X now has preliminary VoiceOver support turned on by default
Initial web app support (Windows/Mac/Linux)
Acholi and Kazakh localizations added
Improvements around JavaScript responsiveness through incremental garbage collection
New Developer Toolbar with buttons for quick access to tools, error count for the Web Console, and a new command line for quick keyboard access
CSS3 Animations, Transitions, Transforms and Gradients unprefixed
Recently opened files list in Scratchpad implemented
Fixed an issue where debugger breakpoints do not catch on page reload
No longer supporting MD5 as a hash algorithm in digital signatures
Opus support by default
Reverse animation direction has been implemented
Per tab reporting in about:memory
User Agent strings for pre-release Firefox versions now show only major version
16.0.1
2012-10-11
Fixed security vulnerabilities
16.0.2
2012-10-26
Fixed security vulnerability
17.0
2012-11-20
17.0
First revision of the Social API and support for Facebook Messenger
Click-to-play blocklisting implemented to prevent vulnerable plugin versions from running without the user's permission
Updated Awesome Bar experience with larger icons
Mac OS X 10.5 is no longer supported
JavaScript Maps and Sets are now iterable
SVG FillPaint and StrokePaint implemented
Improvements that make the Web Console, Debugger and Developer Toolbar faster and easier to use
New Markup panel in the Page Inspector allows easy editing of the DOM
Sandbox attribute for iframes implemented, enabling increased security
Over twenty performance improvements, including fixes around the New Tab page
Fixed pointer lock that doesn't work in web apps
Fixed page scrolling on sites with fixed headers
17.0.1
2012-11-30
Reverted user agent change causing some website incompatibilities
Fixed font rendering issue
Version
Release date
Gecko
Release notes
18.0alpha
Updated daily
18.0
Support for Retina Display on OS X 10.7 and up
Preliminary support for WebRTC
Better image quality with a new HTML scaling algorithm
Performance improvements around tab switching
CSS3 Flexbox implemented
Support for new DOM property window.devicePixelRatio
DOM Tree Live Preview added to inspect tool (see screenshot)
Support for @supports added
Improvement in startup time through smart handling of signed extension certificates
Support for W3C touch events impemented, taking the place of MozTouch events
Disable insecure content loading on HTTPS pages
19.0alpha
Updated daily
19.0
Panel-based download manager
Tab strip visual redesign
Windows plugin hang UI