Mozilla Firefox Changelog

New in version 40.0 Beta 1

July 6th, 2015
  • Support for Windows 10 including tablet mode
  • Download protection from potentially unwanted software
  • Suggested Tiles show sites that may be of interest, based on categories from your recent browsing history
  • Add URLs to a Hello conversation for additional context
  • New style for add-on manager based on the in-content preferences style
  • Smoother and more reliable CSS animations via asynchronous animations
  • Improved scrolling, graphics, and video playback performance with off main thread compositing (GNU/Linux)
  • Add-on extensions that are not signed by Mozilla will display a warning
  • Smoother animation and scrolling with hardware vsync (Windows only)
  • JPEG images use less memory when scaled and can be painted faster
  • Support for new Unicode 8.0 skin tone emoji
  • IndexedDB transactions are now non-durable by default
  • Implemented AudioBufferSourceNode.detune to modulate playback rate in cents
  • Improved Performance tools in the developer tools
  • New rules view tooltip to tweak CSS Filter values
  • New page ruler highlighting tool that displays lightweight horizontal and vertical rules on a page
  • Console API messages from SharedWorker and ServiceWorker are now displayed in web console
  • Inspector now searches across all content frames in a page
  • Places Keywords API has been deprecated, update to the Asynchronous Keywords API
  • Removed support for binary XPCOM components in extensions, use addon SDK "system/child_process" pipe mechanism for native binaries instead
  • Kannada text does not display properly in built-in pdf viewer

New in version 39.0 (July 3rd, 2015)

  • Share Hello URLs with social networks
  • Project Silk: Smoother animation and scrolling (Mac OS X)
  • Support for 'switch' role in ARIA 1.1 (web accessibility)
  • SafeBrowsing malware detection lookups enabled for downloads (Mac OS X and Linux)
  • Support for new Unicode 8.0 skin tone emoji
  • Removed support for insecure SSLv3 for network communications
  • Disable use of RC4 except for temporarily whitelisted hosts
  • The malware detection service for downloads now covers common Mac file types (Bug 1138721)
  • Performance of displaying dashed lines is improved (Mac OS X) (Bug 1123019)
  • List-style-type now accepts a string value
  • Enable the Fetch API for network requests from dedicated, shared and service workers
  • Cascading of CSS transitions and animations now matches the current spec
  • Implement allowing anticipation of a future connection without revealing any information
  • Added support for CSS Scroll Snap Points
  • Drag and drop enabled for nodes in Inspector markup view
  • Webconsole input history persists even after closing the toolbox
  • Cubic bezier tooltip now shows a gallery of timing-function presets for use with CSS animations
  • localhost is now available offline for WebSocket connections
  • Improve performance for IPv6 fallback to IPv4
  • Fix incomplete downloads being marked as complete by detecting broken HTTP1.1 transfers
  • The Security state indicator on a page now correctly ignores loads caused by previous pages
  • Fixed an issue where a Hello conversation window would sometimes fail to open
  • A regression that could lead to Flash not displaying has been fixed
  • Update to NSS 3.19.2
  • Various security fixes

New in version 39.0 Beta 7 (June 21st, 2015)

  • Support for new Unicode 8.0 skin tone emoji
  • SafeBrowsing malware detection lookups enabled for downloads (Mac OS X and Linux)
  • The malware detection service for downloads now covers common Mac extensions
  • Support for 'switch' role in ARIA 1.1 (web accessibility)
  • Hello link sharing
  • Removed support for insecure SSLv3 for network communications
  • NPAPI Plug-in performance improved via asynchronous initialization
  • Smoother animation and scrolling (Mac OS X)
  • Performance of displaying dashed lines is improved (Mac OS X) Bug 1123019)
  • Disable use of RC4 except for temporarily whitelisted hosts
  • Added support for CSS Scroll Snap Points
  • List-style-type now accepts a string value
  • Cascading of CSS transitions and animations now matches the current spec
  • Implement
  • Enable the Fetch API for network requests from dedicated, shared and service workers
  • Drag and drop enabled for nodes in Inspector markup view
  • Webconsole input history persists even after closing the toolbox
  • Cubic bezier tooltip now shows a gallery of timing-function presets for use with CSS animations
  • localhost is now available offline for WebSocket connections
  • Improve performance for IPv6 fallback to IPv4
  • The Security state indicator on a page now correctly ignores loads caused by previous pages
  • Fix incomplete downloads being marked as complete by detecting broken HTTP1.1 transfers
  • Fixed an issue where a Hello conversation window would sometimes fail to open

New in version 39.0 Beta 5 (June 13th, 2015)

  • Support for new Unicode 8.0 skin tone emoji
  • SafeBrowsing malware detection lookups enabled for downloads (Mac OS X and Linux)
  • The malware detection service for downloads now covers common Mac extensions
  • Support for 'switch' role in ARIA 1.1 (web accessibility)
  • Hello link sharing
  • Removed support for insecure SSLv3 for network communications
  • NPAPI Plug-in performance improved via asynchronous initialization
  • Smoother animation and scrolling (Mac OS X)
  • Performance of displaying dashed lines is improved (Mac OS X) Bug 1123019)
  • Disable use of RC4 except for temporarily whitelisted hosts
  • Added support for CSS Scroll Snap Points
  • List-style-type now accepts a string value
  • Cascading of CSS transitions and animations now matches the current spec
  • Implement
  • Enable the Fetch API for network requests from dedicated, shared and service workers
  • Drag and drop enabled for nodes in Inspector markup view
  • Webconsole input history persists even after closing the toolbox
  • Cubic bezier tooltip now shows a gallery of timing-function presets for use with CSS animations
  • localhost is now available offline for WebSocket connections
  • Improve performance for IPv6 fallback to IPv4
  • The Security state indicator on a page now correctly ignores loads caused by previous pages
  • Fix incomplete downloads being marked as complete by detecting broken HTTP1.1 transfers
  • Fixed an issue where a Hello conversation window would sometimes fail to open

New in version 38.0.5 (June 2nd, 2015)

  • Keep track of articles and videos with Pocket
  • Clean formatting for articles and blog posts with Reader View
  • Share the active tab or window in a Hello conversation
  • A race condition that would cause Firefox to stop painting when switching tabs (bug 1067470)

New in version 39.0 Beta 1 (May 29th, 2015)

  • Support for new Unicode 8.0 skin tone emoji
  • SafeBrowsing malware detection lookups enabled for downloads (Mac OS X and Linux)
  • The malware detection service for downloads now covers common Mac extensions
  • Support for 'switch' role in ARIA 1.1 (web accessibility)
  • Removed support for insecure SSLv3 for network communications
  • NPAPI Plug-in performance improved via asynchronous initialization
  • Smoother animation and scrolling (Mac OS X)
  • Performance of displaying dashed lines is improved (Mac OS X) Bug 1123019)
  • Disable use of RC4 except for temporarily whitelisted hosts
  • Added support for CSS Scroll Snap Points
  • List-style-type now accepts a string value
  • Cascading of CSS transitions and animations now matches the current spec
  • Implement
  • Enable the Fetch API for network requests from dedicated, shared and service workers
  • Drag and drop enabled for nodes in Inspector markup view
  • Webconsole input history persists even after closing the toolbox
  • Cubic bezier tooltip now shows a gallery of timing-function presets for use with CSS animations
  • localhost is now available offline for WebSocket connections
  • Improve performance for IPv6 fallback to IPv4
  • The Security state indicator on a page now correctly ignores loads caused by previous pages
  • Fix incomplete downloads being marked as complete by detecting broken HTTP1.1 transfers
  • Fixed an issue where a Hello conversation window would sometimes fail to open

New in version 38.0.1 (May 14th, 2015)

  • Systems with first generation NVidia Optimus graphics cards may crash on start-up
  • Users who import cookies from Google Chrome can end up with broken websites
  • Large animated images may fail to play and may stop other images from loading
  • WebRTC H264 video streams from CiscoSpark native clients are not decoded correctly. (Fixed in Firefox ESR 38.0.1; was already fixed in Firefox 38.0)

New in version 38.0.5 Beta (May 14th, 2015)

  • Keep track of articles and videos with Pocket
  • Clean formatting for articles and blog posts with Reader View
  • Share the active tab or window in a Hello conversation
  • Responsive images do not update when the enclosing viewport changes

New in version 38.0 (May 12th, 2015)

  • New tab-based preferences
  • Ruby annotation support
  • Share the active tab or window in a Hello conversation - enabled for first half of the beta cycle
  • Keep track of articles and blog posts with the Reading List - enabled for the first half of the beta cycle
  • Base for the next ESR release.
  • autocomplete=off is no longer supported for username/password fields
  • RegExp.prototype.source now returns "(?:)" instead of the empty string for empty regular expressions
  • Page load times improved by speculative connection warmup
  • WebSocket now available in Web Workers
  • Implemented srcset attribute and element for responsive images
  • Implemented DOM3 Events KeyboardEvent.code
  • Mac OS X: Implemented a subset of the Media Source Extensions (MSE) API to allow native HTML5 playback on YouTube
  • BroadcastChannel API implemented
  • Implemented Encrypted Media Extensions (EME) API to support encrypted HTML5 video/audio playback (Windows Vista or later only)
  • Automatically download Adobe Primetime Content Decryption Module (CDM) for DRM playback through EME (Windows Vista or later only)
  • Optimized-out variables are now visible in Debugger UI
  • XMLHttpRequest logs in the web console are now visually labelled and can be filtered separately from regular network requests
  • WebRTC now has multistream and renegotiation support
  • copy command added to console

New in version 38.0 Beta 9 (April 30th, 2015)

  • New tab-based Preferences
  • Share the active tab or window in a Hello conversation - enabled for first half of the beta cycle
  • Keep track of articles and blog posts with the Reading List - enabled for the first half of the beta cycle
  • Ruby annotation support
  • Base for the next ESR release.
  • autocomplete=off is no longer supported for username/password fields
  • URL parser avoids doing percent encoding when setting the Fragment part of the URL, and percent decoding when getting the Fragment in line with the URL spec
  • RegExp.prototype.source now returns "(?:)" instead of the empty string for empty regular expressions
  • Page load times improved by speculative connection warmup
  • WebSocket now available in Web Workers
  • Implemented srcset attribute and element for responsive images
  • Implemented DOM3 Events KeyboardEvent.code
  • BroadcastChannel API implemented (more at hacks.mozilla.org)
  • Mac OS X: Implemented a subset of the Media Source Extensions (MSE) API to allow native HTML5 playback on YouTube
  • Implemented Encrypted Media Extensions (EME) API to support encrypted HTML5 video/audio playback
  • Automatically download Adobe Primetime Content Decryption Module (CDM) for DRM playback through EME
  • Optimized-out variables are now visible in Debugger UI
  • XMLHttpRequest logs in the web console are now visually labelled and can be filtered separately from regular network requests
  • copy command added to console
  • WebRTC now has multistream and renegotiation support

New in version 38.0 Beta 8 (April 29th, 2015)

  • New tab-based Preferences
  • Share the active tab or window in a Hello conversation - enabled for first half of the beta cycle
  • Keep track of articles and blog posts with the Reading List - enabled for the first half of the beta cycle
  • Ruby annotation support
  • Base for the next ESR release.
  • autocomplete=off is no longer supported for username/password fields
  • URL parser avoids doing percent encoding when setting the Fragment part of the URL, and percent decoding when getting the Fragment in line with the URL spec
  • RegExp.prototype.source now returns "(?:)" instead of the empty string for empty regular expressions
  • Page load times improved by speculative connection warmup
  • WebSocket now available in Web Workers
  • Implemented srcset attribute and element for responsive images
  • Implemented DOM3 Events KeyboardEvent.code
  • BroadcastChannel API implemented (more at hacks.mozilla.org)
  • Mac OS X: Implemented a subset of the Media Source Extensions (MSE) API to allow native HTML5 playback on YouTube
  • Implemented Encrypted Media Extensions (EME) API to support encrypted HTML5 video/audio playback
  • Automatically download Adobe Primetime Content Decryption Module (CDM) for DRM playback through EME
  • Optimized-out variables are now visible in Debugger UI
  • XMLHttpRequest logs in the web console are now visually labelled and can be filtered separately from regular network requests
  • copy command added to console
  • WebRTC now has multistream and renegotiation support

New in version 38.0 Beta 7 (April 27th, 2015)

  • New tab-based Preferences
  • Share the active tab or window in a Hello conversation - enabled for first half of the beta cycle
  • Keep track of articles and blog posts with the Reading List - enabled for the first half of the beta cycle
  • Ruby annotation support
  • Base for the next ESR release.
  • autocomplete=off is no longer supported for username/password fields
  • URL parser avoids doing percent encoding when setting the Fragment part of the URL, and percent decoding when getting the Fragment in line with the URL spec
  • RegExp.prototype.source now returns "(?:)" instead of the empty string for empty regular expressions
  • Page load times improved by speculative connection warmup
  • WebSocket now available in Web Workers
  • Implemented srcset attribute and element for responsive images
  • Implemented DOM3 Events KeyboardEvent.code
  • BroadcastChannel API implemented (more at hacks.mozilla.org)
  • Mac OS X: Implemented a subset of the Media Source Extensions (MSE) API to allow native HTML5 playback on YouTube
  • Implemented Encrypted Media Extensions (EME) API to support encrypted HTML5 video/audio playback
  • Automatically download Adobe Primetime Content Decryption Module (CDM) for DRM playback through EME
  • Optimized-out variables are now visible in Debugger UI
  • XMLHttpRequest logs in the web console are now visually labelled and can be filtered separately from regular network requests
  • copy command added to console
  • WebRTC now has multistream and renegotiation support

New in version 38.0 Beta 6 (April 23rd, 2015)

  • New tab-based Preferences
  • Share the active tab or window in a Hello conversation - enabled for first half of the beta cycle
  • Keep track of articles and blog posts with the Reading List - enabled for the first half of the beta cycle
  • Ruby annotation support
  • Base for the next ESR release.
  • autocomplete=off is no longer supported for username/password fields
  • URL parser avoids doing percent encoding when setting the Fragment part of the URL, and percent decoding when getting the Fragment in line with the URL spec
  • RegExp.prototype.source now returns "(?:)" instead of the empty string for empty regular expressions
  • Page load times improved by speculative connection warmup
  • WebSocket now available in Web Workers
  • Implemented srcset attribute and element for responsive images
  • Implemented DOM3 Events KeyboardEvent.code
  • BroadcastChannel API implemented (more at hacks.mozilla.org)
  • Mac OS X: Implemented a subset of the Media Source Extensions (MSE) API to allow native HTML5 playback on YouTube
  • Implemented Encrypted Media Extensions (EME) API to support encrypted HTML5 video/audio playback
  • Automatically download Adobe Primetime Content Decryption Module (CDM) for DRM playback through EME
  • Optimized-out variables are now visible in Debugger UI
  • XMLHttpRequest logs in the web console are now visually labelled and can be filtered separately from regular network requests
  • copy command added to console
  • WebRTC now has multistream and renegotiation support

New in version 37.0.2 (April 20th, 2015)

  • Google Maps may render incorrectly in some cases
  • Stability fixes for select graphics hardware and feature sets
  • Various security fixes

New in version 38.0 Beta 5 (April 17th, 2015)

  • New tab-based Preferences
  • Share the active tab or window in a Hello conversation - enabled for first half of the beta cycle
  • Keep track of articles and blog posts with the Reading List - enabled for the first half of the beta cycle
  • Ruby annotation support
  • Base for the next ESR release.
  • autocomplete=off is no longer supported for username/password fields
  • URL parser avoids doing percent encoding when setting the Fragment part of the URL, and percent decoding when getting the Fragment in line with the URL spec
  • RegExp.prototype.source now returns "(?:)" instead of the empty string for empty regular expressions
  • Page load times improved by speculative connection warmup
  • WebSocket now available in Web Workers
  • Implemented srcset attribute and element for responsive images
  • Implemented DOM3 Events KeyboardEvent.code
  • BroadcastChannel API implemented (more at hacks.mozilla.org)
  • Mac OS X: Implemented a subset of the Media Source Extensions (MSE) API to allow native HTML5 playback on YouTube
  • Implemented Encrypted Media Extensions (EME) API to support encrypted HTML5 video/audio playback
  • Automatically download Adobe Primetime Content Decryption Module (CDM) for DRM playback through EME
  • Optimized-out variables are now visible in Debugger UI
  • XMLHttpRequest logs in the web console are now visually labelled and can be filtered separately from regular network requests
  • copy command added to console
  • WebRTC now has multistream and renegotiation support

New in version 38.0 Beta 2 (April 7th, 2015)

  • New tab-based Preferences
  • Share the active tab or window in a Hello conversation - enabled for first half of the beta cycle
  • Keep track of articles and blog posts with the Reading List - enabled for the first half of the beta cycle
  • Ruby annotation support
  • Base for the next ESR release.
  • autocomplete=off is no longer supported for username/password fields
  • URL parser avoids doing percent encoding when setting the Fragment part of the URL, and percent decoding when getting the Fragment in line with the URL spec
  • RegExp.prototype.source now returns "(?:)" instead of the empty string for empty regular expressions
  • Page load times improved by speculative connection warmup
  • WebSocket now available in Web Workers
  • Implemented srcset attribute and element for responsive images
  • Implemented DOM3 Events KeyboardEvent.code
  • BroadcastChannel API implemented (more at hacks.mozilla.org)
  • Mac OS X: Implemented a subset of the Media Source Extensions (MSE) API to allow native HTML5 playback on YouTube
  • Implemented Encrypted Media Extensions (EME) API to support encrypted HTML5 video/audio playback
  • Automatically download Adobe Primetime Content Decryption Module (CDM) for DRM playback through EME
  • Optimized-out variables are now visible in Debugger UI
  • XMLHttpRequest logs in the web console are now visually labelled and can be filtered separately from regular network requests
  • copy command added to console
  • WebRTC now has multistream and renegotiation support

New in version 37.0.1 (April 3rd, 2015)

  • Disabled HTTP/2 AltSvc
  • Start-up crash due to graphics hardware and third party software
  • Various security fixes

New in version 38.0 Beta 1 (April 2nd, 2015)

  • New tab-based Preferences
  • Share the active tab or window in a Hello conversation - enabled for first half of the beta cycle
  • Keep track of articles and blog posts with the Reading List - enabled for the first half of the beta cycle
  • Ruby support
  • Base for the next ESR release.
  • autocomplete=off is no longer supported for username/password fields
  • URL parser avoids doing percent encoding when setting the Fragment part of the URL, and percent decoding when getting the Fragment in line with the URL spec
  • RegExp.prototype.source now returns "(?:)" instead of the empty string for empty regular expressions
  • Page load times improved by speculative connection warmup
  • WebSocket now available in Web Workers
  • Implemented srcset attribute and element for responsive images
  • Implemented DOM3 Events KeyboardEvent.code
  • BroadcastChannel API implemented (more at hacks.mozilla.org)
  • Mac OS X: Implemented a subset of the Media Source Extensions (MSE) API to allow native HTML5 playback on YouTube
  • Implemented Encrypted Media Extensions (EME) API to support encrypted HTML5 video/audio playback
  • Automatically download Adobe Primetime Content Decryption Module (CDM) for DRM playback through EME
  • Optimized-out variables are now visible in Debugger UI
  • XMLHttpRequest logs in the web console are now visually labelled and can be filtered separately from regular network requests
  • copy command added to console
  • WebRTC now has multistream and renegotiation support

New in version 37.0 (March 31st, 2015)

  • Heartbeat user rating system - your feedback about Firefox
  • Bing search now uses HTTPS for secure searching
  • New preferences implementation enabled for the first half of the beta cycle
  • Improved protection against site impersonation via OneCRL centralized certificate revocation
  • Opportunistically encrypt HTTP traffic where the server supports HTTP/2 AltSvc
  • Disabled insecure TLS version fallback for site security
  • Extended SSL error reporting for reporting non-certificate errors
  • TLS False Start optimization now requires a cipher suite using AEAD construction
  • Added support for e-mail name constraints in certificates
  • Improved certificate and TLS communication security by removing support for DSA
  • Implemented a subset of the Media Source Extensions (MSE) API to allow native HTML5 playback on YouTube
  • Added support for CSS display:contents
  • IndexedDB now accessible from worker threads
  • WebSocket now available in Web Workers
  • Debug tabs opened in Chrome Desktop, Chrome for Android, and Safari for iOS
  • New Inspector animations panel to control element animations
  • New Security Panel included in Network Panel
  • Debugger panel support for chrome:// and about:// URIs
  • Added logging of weak ciphers to the web console

New in version 36.0.4 (March 21st, 2015)

  • Security fixes for issues disclosed at HP Zero Day Initiative's Pwn2Own contest.

New in version 36.0.3 (March 21st, 2015)

  • Bug 1144988 - Don't let other pages to load while doing scroll-to-anchor.
  • Bug 1142552 - Update robocop chunking to fix rc10.
  • Bug 1142743 - Increase chunks for Android 2.3 mochitest-gl.
  • Bug 1113460 - Bump mozharness.json to revision 75c435ef19ca.
  • Bug 1142459 - Fix mixed content shield notification broke by bug 1140830.
  • Bug 1118216 - Stop recycling Message instances, as it's unnecessary.
  • Bug 1140830 - Don't try to use a null JSONObject in SiteIdentity.update().
  • Bug 1051556 - Simplify GeckoEditable exception messages.

New in version 37.0 Beta 5 (March 13th, 2015)

  • Heartbeat user rating system - your feedback about Firefox
  • Bing search now uses HTTPS for secure searching
  • Added support for OneCRL for centralized certificate revocation
  • Removed support for DSA in certificates and TLS
  • Added support for e-mail name constraints in certificates
  • Implemented HTTP/2 AltSvc support for opportunistic (unauthenticated) encryption
  • New preferences implementation enabled for the first half of the beta cycle
  • Disabled insecure TLS version fallback for site security
  • Extended SSL error reporting for reporting non-certificate errors
  • TLS False Start optimization now requires a cipher suite using AEAD construction
  • Implemented a subset of the Media Source Extensions (MSE) API to allow native HTML5 playback on YouTube.
  • WebSocket now available in Web Workers
  • IndexedDB now accessible from worker threads
  • Added support for CSS display:contents
  • Debug tabs opened in Chrome Desktop, Chrome for Android, and Safari for iOS
  • New Inspector animations panel to control element animations
  • New Security Panel included in Network Panel
  • Debugger panel support for chrome:// and about:// URIs
  • Added logging of weak ciphers to the web console

New in version 36.0.1 (March 6th, 2015)

  • Disable the usage of the ANY DNS query type (1093983)
  • Fixed a startup crash with EMET (1137050)
  • Hello may become inactive until restart (1137469)
  • Print preferences may not be preserved (1136855)
  • Hello contact tabs may not be visible (1137141)
  • Accept hostnames that include an underscore character ("_") (1136616)
  • WebGL may use significant memory with Canvas2d (1137251)
  • Option -remote has been restored (1080319)
  • Fix a top crash

New in version 37.0 Beta 1 (February 24th, 2015)

  • Bug 1135007 - "Sync Now" button is not translated.
  • Bug 1135408 - Report device resets and their reasons through telemetry.
  • Bug 1124106 - Don't show unnamed eval sources in the debugger.
  • Bug 1123904 - Provide url highlighting in reader mode.
  • Bug 1123904 - Display original title in toolbar in reader mode.
  • Bug 1134955 - Be more careful with how we stringify property ids for error message reporting.

New in version 36.0 (February 24th, 2015)

  • Pinned tiles on the new tab page can be synced
  • Support for the full HTTP/2 protocol. HTTP/2 enables a faster, more scalable, and more responsive web.
  • Locale added: Uzbek (uz)
  • New preferences implementation enabled for the first half of the beta cycle
  • The Flash protected-mode sandbox is disabled on Windows, to evaluate the stability impact of protected mode
  • -remote option removed
  • No longer accept insecure RC4 ciphers whenever possible
  • Phasing out Certificates with 1024-bit RSA Keys
  • Shut down hangs will now show the crash reporter before exiting the program
  • Add-on Compatibility
  • Implemented a subset of the Media Source Extensions (MSE) API to allow native HTML5 playback on YouTube.
  • Support for the ECMAScript 6 Symbol data type added
  • unicode-range CSS descriptor implemented
  • CSSOM-View scroll behavior implemented allowing smooth scrolling of content without custom libraries
  • object-fit and object-position implemented.
  • Defines how and where the content of a replaced element is displayed
  • isolation CSS property implemented.
  • Create a new stacking context to isolate groups of boxes to control which blend together
  • CSS3 will-change property implemented.
  • Hints the browser of elements that will be modified. The browser will perform some performance optimization for these
  • Changed JavaScript 'const' semantics to conform better to the ES6 specification.
  • The const declaration is now block-scoped and requires an initializer. It also can not be redeclared anymore.
  • implemented for more privacy. Allows to control the content of the HTTP referer header.
  • Improved ES6 generators for better performance
  • Eval sources now appear in the Debugger
  • Debug JavaScript code that is evaluated dynamically, either as a string passed to eval() or as a string passed to the Function constructor
  • DOM Promises inspection
  • Inspector: More paste options in markup view
  • CSS gradients work on premultiplied colors
  • Fix some unexpected logout from Facebook or Google after restart

New in version 36.0 Beta 10 (February 20th, 2015)

  • Pinned tiles on the new tab page can be synced
  • Support for the full HTTP/2 protocol. HTTP/2 enables a faster, more scalable, and more responsive web.
  • Locale added: Uzbek (uz)
  • New preferences implementation enabled for the first half of the beta cycle
  • The Flash protected-mode sandbox is disabled on Windows, to evaluate the stability impact of protected mode
  • -remote option removed
  • No longer accept insecure RC4 ciphers whenever possible
  • Phasing out Certificates with 1024-bit RSA Keys
  • Add-on Compatibility
  • Implemented a subset of the Media Source Extensions (MSE) API to allow native HTML5 playback on YouTube.
  • Support for the ECMAScript 6 Symbol data type added
  • unicode-range CSS descriptor implemented
  • CSSOM-View scroll behavior implemented allowing smooth scrolling of content without custom libraries
  • object-fit and object-position implemented.
  • Defines how and where the content of a replaced element is displayed
  • isolation CSS property implemented.
  • Create a new stacking context to isolate groups of boxes to control which blend together
  • CSS3 will-change property implemented.
  • Hints the browser of elements that will be modified. The browser will perform some performance optimization for these
  • Improved new ES6 generators for better performance
  • Changed JavaScript 'const' semantics to conform better to the ES6 specification.
  • The const declaration is now block-scoped and requires an initializer. It also can not be redeclared anymore.
  • implemented for more privacy. Allows to control the content of the HTTP referer header.
  • Eval sources now appear in the Debugger
  • Debug JavaScript code that is evaluated dynamically, either as a string passed to eval() or as a string passed to the Function constructor
  • DOM Promises inspection
  • Inspector: More paste options in markup view
  • CSS gradients work on premultiplied colors
  • Fix some unexpected logout from Facebook or Google after restart

New in version 36.0 Beta 9 (February 14th, 2015)

  • Pinned tiles on the new tab page can be synced
  • New preferences implementation enabled for the first half of the beta cycle
  • Locale added: Uzbek (uz)
  • The Flash protected-mode sandbox is disabled on Windows, to evaluate the stability impact of protected mode
  • No longer accept insecure RC4 ciphers whenever possible
  • Add-on Compatibility
  • Phasing out Certificates with 1024-bit RSA Keys
  • -remote option removed
  • Implemented a subset of the Media Source Extensions (MSE) API to allow native HTML5 playback on YouTube. Full support is on the way
  • Support for the ECMAScript 6 Symbol data type added
  • unicode-range CSS descriptor implemented
  • Improved new ES6 generators for better performance
  • CSSOM-View scroll behavior implemented allowing smooth scrolling of content without custom libraries
  • implemented for more privacy. Allows to control the content of the HTTP referer header.
  • object-fit and object-position implemented.
  • Defines how and where the content of a replaced element is displayed
  • isolation CSS property implemented.
  • Create a new stacking context to isolate groups of boxes to control which blend together
  • CSS3 will-change property implemented.
  • Hints the browser of elements that will be modified. The browser will perform some performance optimization for these
  • Changed JavaScript 'const' semantics to conform better to the ES6 specification.
  • The const declaration is now block-scoped and requires an initializer. It also can not be redeclared anymore.
  • DOM Promises inspection
  • Inspector: More paste options in markup view
  • Eval sources now appear in the Debugger
  • Debug JavaScript code that is evaluated dynamically, either as a string passed to eval() or as a string passed to the Function constructor
  • Fix some unexpected logout from Facebook or Google after restart
  • CSS gradients work on premultiplied colors

New in version 36.0 Beta 8 (February 10th, 2015)

  • Pinned tiles on the new tab page can be synced
  • New preferences implementation enabled for the first half of the beta cycle
  • Locale added: Uzbek (uz)
  • The Flash protected-mode sandbox is disabled on Windows, to evaluate the stability impact of protected mode
  • -remote option removed
  • No longer accept insecure RC4 ciphers whenever possible
  • Add-on Compatibility
  • Implemented a subset of the Media Source Extensions (MSE) API to allow native HTML5 playback on YouTube. Full support is on the way
  • Support for the ECMAScript 6 Symbol data type added
  • unicode-range CSS descriptor implemented
  • object-fit and object-position implemented
  • isolation CSS property implemented
  • CSS3 will-change property implemented
  • Improved new ES6 generators for better performance
  • Changed JavaScript 'const' semantics to conform better to the ES6 specification
  • implemented for more privacy
  • CSSOM-View scroll behavior implemented allowing smooth scrolling of content without custom libraries
  • Use the filename supplied by the //# sourceURL= directive for stack frames in the string returned by the Error.prototype.stack getter.
  • DOM Promises inspection
  • Inspector: More paste options in markup view
  • Fix some unexpected logout from Facebook or Google after restart
  • CSS gradients work on premultiplied colors

New in version 36.0 Beta 7 (February 6th, 2015)

  • Pinned tiles on the new tab page can be synced
  • New preferences implementation enabled for the first half of the beta cycle
  • Locale added: Uzbek (uz)
  • The Flash protected-mode sandbox is disabled on Windows, to evaluate the stability impact of protected mode
  • -remote option removed
  • No longer accept insecure RC4 ciphers whenever possible
  • Add-on Compatibility
  • Implemented a subset of the Media Source Extensions (MSE) API to allow native HTML5 playback on YouTube. Full support is on the way
  • Support for the ECMAScript 6 Symbol data type added
  • unicode-range CSS descriptor implemented
  • CSSOM-View scroll behavior implemented (allowing smooth scrolling of content without custom libraries)
  • object-fit and object-position implemented
  • isolation CSS property implemented
  • CSS3 will-change property implemented
  • Improved new ES6 generators for better performance
  • Changed JavaScript 'const' semantics to conform better to the ES6 specification
  • implemented for more privacy
  • Use the filename supplied by the //# sourceURL= directive for stack frames in the string returned by the Error.prototype.stack getter.
  • DOM Promises inspection
  • Inspector: More paste options in markup view
  • CSS gradients work on premultiplied colors
  • Fix some unexpected logout from Facebook or Google after restart

New in version 36.0 Beta 6 (February 3rd, 2015)

  • Pinned tiles on the new tab page can be synced
  • New preferences implementation enabled for the first half of the beta cycle
  • Locale added: Uzbek (uz)
  • The Flash protected-mode sandbox is disabled on Windows, to evaluate the stability impact of protected mode
  • -remote option removed
  • No longer accept insecure RC4 ciphers whenever possible
  • Add-on Compatibility
  • Implemented a subset of the Media Source Extensions (MSE) API to allow native HTML5 playback on YouTube. Full support is on the way
  • Support for the ECMAScript 6 Symbol data type added
  • unicode-range CSS descriptor implemented
  • CSSOM-View scroll behavior implemented (allowing smooth scrolling of content without custom libraries)
  • object-fit and object-position implemented
  • isolation CSS property implemented
  • CSS3 will-change property implemented
  • Improved new ES6 generators for better performance
  • Changed JavaScript 'const' semantics to conform better to the ES6 specification
  • implemented for more privacy
  • Use the filename supplied by the //# sourceURL= directive for stack frames in the string returned by the Error.prototype.stack getter.
  • DOM Promises inspection
  • Inspector: More paste options in markup view
  • CSS gradients work on premultiplied colors
  • Fix some unexpected logout from Facebook or Google after restart

New in version 36.0 Beta 5 (January 31st, 2015)

  • Pinned tiles on the new tab page can be synced
  • New preferences implementation enabled for the first half of the beta cycle
  • Locale added: Uzbek (uz)
  • The Flash protected-mode sandbox is disabled on Windows, to evaluate the stability impact of protected mode
  • -remote option removed
  • No longer accept insecure RC4 ciphers whenever possible
  • Add-on Compatibility
  • Implemented a subset of the Media Source Extensions (MSE) API to allow native HTML5 playback on YouTube. Full support is on the way
  • Support for the ECMAScript 6 Symbol data type added
  • unicode-range CSS descriptor implemented
  • CSSOM-View scroll behavior implemented (allowing smooth scrolling of content without custom libraries)
  • object-fit and object-position implemented
  • isolation CSS property implemented
  • CSS3 will-change property implemented
  • Improved new ES6 generators for better performance
  • Changed JavaScript 'const' semantics to conform better to the ES6 specification
  • implemented for more privacy
  • Use the filename supplied by the //# sourceURL= directive for stack frames in the string returned by the Error.prototype.stack getter.
  • DOM Promises inspection
  • Inspector: More paste options in markup view
  • CSS gradients work on premultiplied colors
  • Fix some unexpected logout from Facebook or Google after restart

New in version 36.0 Beta 4 (January 27th, 2015)

  • Pinned tiles on the new tab page can be synced
  • New preferences implementation enabled for the first half of the beta cycle
  • -remote option removed
  • No longer accept insecure RC4 ciphers whenever possible
  • Add-on Compatibility
  • Implemented a subset of the Media Source Extensions (MSE) API to allow native HTML5 playback on YouTube. Full support is on the way
  • Support for the ECMAScript 6 Symbol data type added
  • unicode-range CSS descriptor implemented
  • CSSOM-View scroll behavior implemented (allowing smooth scrolling of content without custom libraries)
  • object-fit and object-position implemented
  • isolation CSS property implemented
  • CSS3 will-change property implemented
  • Improved new ES6 generators for better performance
  • Changed JavaScript 'const' semantics to conform better to the ES6 specification
  • implemented for more privacy
  • Use the filename supplied by the //# sourceURL= directive for stack frames in the string returned by the Error.prototype.stack getter.
  • DOM Promises inspection
  • Inspector: More paste options in markup view
  • CSS gradients work on premultiplied colors
  • Fix some unexpected logout from Facebook or Google after restart

New in version 35.0.1 (January 26th, 2015)

  • With the Enhanced Steam extension, Firefox could crash (1123732)
  • Fix a potential startup crash (1122367)
  • Kerberos authentication did not work with alias (1108971)
  • SVG / CSS animation had a regression causing rendering issues on websites like openstreemap.org (1083079)
  • On Godaddy webmail, Firefox could crash (1113121)
  • document.baseURI did not get updated to document.location after base tag was removed from DOM for site with a CSP (1121857)
  • With a Right-to-left (RTL) version of Firefox, the text selection could be broken (1104036)
  • CSP had a change in behavior with regard to case sensitivity resources loading (1122445)

New in version 36.0 Beta 3 (January 24th, 2015)

  • Pinned tiles on the new tab page can be synced
  • New preferences implementation enabled for the first half of the beta cycle
  • -remote option removed
  • No longer accept insecure RC4 ciphers whenever possible
  • Add-on Compatibility
  • Implemented a subset of the Media Source Extensions (MSE) API to allow native HTML5 playback on YouTube. Full support is on the way
  • Support for the ECMAScript 6 Symbol data type added
  • unicode-range CSS descriptor implemented
  • CSSOM-View scroll behavior implemented (allowing smooth scrolling of content without custom libraries)
  • object-fit and object-position implemented
  • isolation CSS property implemented
  • CSS3 will-change property implemented
  • Improved new ES6 generators for better performance
  • Changed JavaScript 'const' semantics to conform better to the ES6 specification
  • Use the filename supplied by the //# sourceURL= directive for stack frames in the string returned by the Error.prototype.stack getter.
  • DOM Promises inspection
  • Inspector: More paste options in markup view
  • CSS gradients work on premultiplied colors
  • Fix some unexpected logout from Facebook or Google after restart

New in version 36.0 Beta 2 (January 21st, 2015)

  • Pinned tiles on the new tab page can be synced
  • New preferences implementation enabled for the first half of the beta cycle
  • -remote option removed
  • No longer accept insecure RC4 ciphers whenever possible
  • Add-on Compatibility
  • Implemented a subset of the Media Source Extensions (MSE) API to allow native HTML5 playback on YouTube. Full support is on the way
  • Support for the ECMAScript 6 Symbol data type added
  • unicode-range CSS descriptor implemented
  • CSSOM-View scroll behavior implemented (allowing smooth scrolling of content without custom libraries)
  • object-fit and object-position implemented
  • isolation CSS property implemented
  • CSS3 will-change property implemented
  • Improved new ES6 generators for better performance
  • Changed JavaScript 'const' semantics to conform better to the ES6 specification
  • Use the filename supplied by the //# sourceURL= directive for stack frames in the string returned by the Error.prototype.stack getter.
  • DOM Promises inspection
  • Inspector: More paste options in markup view
  • CSS gradients work on premultiplied colors
  • Fix some unexpected logout from Facebook or Google after restart

New in version 36.0 Beta 1 (January 16th, 2015)

  • Pinned tiles on the new tab page can be synced
  • New preferences implementation enabled for the first half of the beta cycle
  • -remote option removed
  • No longer accept insecure RC4 ciphers whenever possible
  • Add-on Compatibility
  • Support for the ECMAScript 6 Symbol data type added
  • unicode-range CSS descriptor implemented
  • CSSOM-View scroll behavior implemented (allowing smooth scrolling of content without custom libraries)
  • object-fit and object-position implemented
  • isolation CSS property implemented
  • CSS3 will-change property implemented
  • Improved new ES6 generators for better performance
  • Changed JavaScript 'const' semantics to conform better to the ES6 specification
  • Implemented a subset of the Media Source Extensions (MSE) API to allow native HTML5 playback on YouTube. Full support is on the way
  • Use the filename supplied by the //# sourceURL= directive for stack frames in the string returned by the Error.prototype.stack getter.
  • DOM Promises inspection
  • Inspector: More paste options in markup view
  • CSS gradients work on premultiplied colors

New in version 35.0 (January 13th, 2015)

  • Firefox Hello with new rooms-based conversations model
  • Built-in support for H264 (MP4) on Mac OS X Snow Leopard (10.6) and newer through native APIs
  • Improved handling of dynamic styling changes to increase responsiveness
  • Implemented HTTP Public Key Pinning Extension (for enhanced authentication of encrypted connections)
  • Changed JavaScript 'let' semantics to match the ES6 specification
  • Resource Timing API implemented
  • CSS filters enabled by default
  • WebSocket available in Workers
  • Added support for the CSS Font Loading API
  • Support for inspecting ::before and ::after pseudo elements
  • Computed view: Nodes matching the hovered selector are now highlighted
  • Show DOM Properties context menu item in inspector
  • Reduced resource usage for scaled images
  • PDF.js updated to version 1.0.907

New in version 35.0 RC1 (January 6th, 2015)

  • Bug fixes:
  • Bug 1102063 - PDF.js: Prevent the arrows from overlapping text in the zoom box.
  • Bug 1078304 - Call GeckoAppShell.setLayerView early.
  • Bug 1072997 - Check for a disabled System Download Manager before trying to use it.
  • Bug 1116669 - Wait for focus before running test_offlineNotification.html.
  • Bug 1114655 - Increase robocop WaitHelper default wait time.
  • Bug 1106150 - Fix condition="defaultEngine" MozParam,

New in version 35.0 Beta 8 (December 31st, 2014)

  • Firefox Hello with new rooms-based conversations model
  • Built-in support for H264 (MP4) on Mac OS X Snow Leopard (10.6) and newer through native APIs
  • Improved handling of dynamic styling changes to increase responsiveness
  • Implemented HTTP Public Key Pinning Extension (for enhanced authentication of encrypted connections)
  • Resource Timing API implemented
  • CSS filters enabled by default
  • WebSocket available in Workers
  • Changed JavaScript 'let' semantics to match the ES6 specification
  • Computed view: Nodes matching the hovered selector are now highlighted
  • Support for inspecting ::before and ::after pseudo elements
  • Show DOM Properties context menu item in inspector
  • Reduced resource usage for scaled images
  • PDF.js updated to version 1.0.907

New in version 35.0 Beta 6 (December 24th, 2014)

  • Firefox Hello with new rooms-based conversations model
  • Built-in support for H264 (MP4) on Mac OS X Snow Leopard (10.6) and newer through native APIs
  • Improved handling of dynamic styling changes to increase responsiveness
  • Implemented HTTP Public Key Pinning Extension (for enhanced authentication of encrypted connections)
  • Resource Timing API implemented
  • CSS filters enabled by default
  • WebSocket available in Workers
  • Changed JavaScript 'let' semantics to match the ES6 specification
  • Computed view: Nodes matching the hovered selector are now highlighted
  • Support for inspecting ::before and ::after pseudo elements
  • Show DOM Properties context menu item in inspector
  • Reduced resource usage for scaled images
  • PDF.js updated to version 1.0.907

New in version 35.0 Beta 5 (December 19th, 2014)

  • Firefox Hello with new rooms-based conversations model
  • Built-in support for H264 (MP4) on Mac OS X Snow Leopard (10.6) and newer through native APIs
  • Improved handling of dynamic styling changes to increase responsiveness
  • Implemented HTTP Public Key Pinning Extension (for enhanced authentication of encrypted connections)
  • Resource Timing API implemented
  • CSS filters enabled by default
  • WebSocket available in Workers
  • Changed JavaScript 'let' semantics to match the ES6 specification
  • Computed view: Nodes matching the hovered selector are now highlighted
  • Support for inspecting ::before and ::after pseudo elements
  • Show DOM Properties context menu item in inspector
  • Reduced resource usage for scaled images
  • PDF.js updated to version 1.0.907

New in version 35.0 Beta 4 (December 17th, 2014)

  • Firefox Hello with new rooms-based conversations model
  • Built-in support for H264 (MP4) on Mac OS X Snow Leopard (10.6) and newer through native APIs
  • Improved handling of dynamic styling changes to increase responsiveness
  • Implemented HTTP Public Key Pinning Extension (for enhanced authentication of encrypted connections)
  • Resource Timing API implemented
  • CSS filters enabled by default
  • WebSocket available in Workers
  • Changed JavaScript 'let' semantics to match the ES6 specification
  • Computed view: Nodes matching the hovered selector are now highlighted
  • Support for inspecting ::before and ::after pseudo elements
  • Show DOM Properties context menu item in inspector
  • Reduced resource usage for scaled images
  • PDF.js updated to version 1.0.907

New in version 35.0 Beta 3 (December 12th, 2014)

  • Firefox Hello with new rooms-based conversations model
  • Built-in support for H264 (MP4) on Mac OS X Snow Leopard (10.6) and newer through native APIs
  • Improved handling of dynamic styling changes to increase responsiveness
  • Implemented HTTP Public Key Pinning Extension (for enhanced authentication of encrypted connections)
  • Resource Timing API implemented
  • CSS filters enabled by default
  • WebSocket available in Workers
  • Changed JavaScript 'let' semantics to match the ES6 specification
  • Computed view: Nodes matching the hovered selector are now highlighted
  • Support for inspecting ::before and ::after pseudo elements
  • Show DOM Properties context menu item in inspector
  • Reduced resource usage for scaled images
  • PDF.js updated to version 1.0.907

New in version 35.0 Beta 2 (December 10th, 2014)

  • Firefox Hello with new rooms-based conversations model
  • Built-in support for H264 (MP4) on Mac OS X Snow Leopard (10.6) and newer through native APIs
  • Improved handling of dynamic styling changes to increase responsiveness
  • Implemented HTTP Public Key Pinning Extension (for enhanced authentication of encrypted connections)
  • Resource Timing API implemented
  • CSS filters enabled by default
  • WebSocket available in Workers
  • Changed JavaScript 'let' semantics to match the ES6 specification
  • Computed view: Nodes matching the hovered selector are now highlighted
  • Support for inspecting ::before and ::after pseudo elements
  • Show DOM Properties context menu item in inspector
  • Reduced resource usage for scaled images
  • PDF.js updated to version 1.0.907

New in version 34.0.5 (December 1st, 2014)

  • Firefox Hello real-time communication client
  • Easily switch themes/personas directly in the Customizing mode
  • Wikipedia search now uses HTTPS for secure searching (en-US only)
  • Implementation of HTTP/2 (draft14) and ALPN
  • Recover from a locked Firefox process in the "Firefox is already running" dialog on Windows
  • ECMAScript 6 WeakSet Implemented
  • JavaScript Template Strings Implemented
  • CSS3 Font variants and features control (e.g. kerning) implemented
  • WebCrypto: RSA-OAEP, PBKDF2 and AES-KW support
  • WebCrypto: wrapKey and unwrapKey implemented
  • WebCrypto: Import/export of JWK-formatted keys
  • matches() DOM API implemented (formerly mozMatchesSelector())
  • Performance.now() for workers implemented
  • WebCrypto: ECDH support
  • Support for the ECMAScript 6 Symbol data type added
  • WebIDE: Create, edit, and test a new Web application from your browser
  • Highlight all nodes that match a given selector in the Style Editor and the Inspector's Rules panel
  • Improved User Interface of the Profiler
  • console.table function added to web console
  • CSS transitions start correctly when started at the same time as changes to display, position, overflow, and similar properties

New in version 34.0 RC2 (November 26th, 2014)

  • Fixed bugs:
  • Bug 1104925: followup to fix tests.
  • Bug 1102416: make Yahoo the default search plugin for en-US in American time zones.
  • Bug 1104748 - A long default search provider name can mess up the layout of the one-off buttons when the panel is small.
  • Bug 1104823 - Fix packaging of UITour FHR recording (modules.manifest renamed to browsermodules.manifest for clarity).
  • Bug 1104925: update Yahoo search plugin for en-US.

New in version 34.0 RC1 (November 25th, 2014)

  • Fixed bugs:
  • Bug 1104306 - Re-whitelist UITour on Fx34.
  • Bug 1104306 - Re-whitelist https://www.mozilla.org for uitour on Fx34.
  • Bug 1102911 - The search engine favicons are distorted in search preferences on Linux.
  • Bug 1101669 - UITour: showInfo("search") should drop its notification from the end of the search box, not the middle.
  • Bug 1104221 - Search drop down shows the icon of the previous default engine if the new default doesn't have an icon.
  • Bug 1026893 - Bandaid to catch D3D11 related crashes and deal with them.
  • Bug 1102841 - Implement Cancel and Block a call for incoming direct calls.
  • Bug 1102855 - Fix uninitialized variable.
  • Bug 1104114 - update copy for HPOPA.
  • Bug 1103216 - update Google parameters.

New in version 34.0 Beta 10 (November 19th, 2014)

  • Firefox Hello real-time communication client
  • Easily switch themes/personas directly in the Customizing mode
  • Wikipedia search now uses HTTPS for secure searching
  • Implementation of HTTP/2 (draft14) and ALPN
  • Recover from a locked Firefox process in the "Firefox is already running" dialog on Windows
  • ECMAScript 6 WeakSet Implemented
  • JavaScript Template Strings Implemented
  • CSS3 Font variants and features control (e.g. kerning) implemented
  • WebCrypto: RSA-OAEP, PBKDF2 and AES-KW support
  • WebCrypto: wrapKey and unwrapKey implemented
  • WebCrypto: Import/export of JWK-formatted keys
  • matches() DOM API implemented (formerly mozMatchesSelector())
  • Performance.now() for workers implemented
  • WebCrypto: ECDH support
  • Support for the ECMAScript 6 Symbol data type added
  • WebIDE: Create, edit, and test a new Web application from your browser
  • Highlight all nodes that match a given selector in the Style Editor and the Inspector's Rules panel
  • Improved User Interface of the Profile
  • console.table function added to web console
  • CSS transitions start correctly when started at the same time as changes to display, position, overflow, and similar properties

New in version 33.1.1 (November 15th, 2014)

  • Fixed startup crash (see bug 1021265)

New in version 33.1.0 (November 15th, 2014)

  • Forget Button added
  • Enhanced Tiles
  • Privacy tour introduced
  • Adding DuckDuckGo as a search option

New in version 34.0 Beta 9 (November 14th, 2014)

  • Firefox Hello real-time communication client
  • Easily switch themes/personas directly in the Customizing mode
  • Built-in support for H264 (MP4) on Mac OS X Snow Leopard (10.6) and newer through native APIs
  • Wikipedia search now uses HTTPS for secure searching
  • Implementation of HTTP/2 (draft14) and ALPN
  • Recover from a locked Firefox process in the "Firefox is already running" dialog on Windows
  • ECMAScript 6 WeakSet Implemented
  • JavaScript Template Strings Implemented
  • CSS3 Font variants and features control (e.g. kerning) implemented
  • WebCrypto: RSA-OAEP, PBKDF2 and AES-KW support
  • WebCrypto: wrapKey and unwrapKey implemented
  • WebCrypto: Import/export of JWK-formatted keys
  • matches() DOM API implemented (formerly mozMatchesSelector())
  • Performance.now() for workers implemented
  • WebCrypto: ECDH support
  • Support for the ECMAScript 6 Symbol data type added
  • WebIDE: Create, edit, and test a new Web application from your browser
  • Highlight all nodes that match a given selector in the Style Editor and the Inspector's Rules panel
  • Improved User Interface of the Profiler
  • console.table function added to web console
  • CSS transitions start correctly when started at the same time as changes to display, position, overflow, and similar properties

New in version 34.0 Beta 8 (November 11th, 2014)

  • Firefox Hello real-time communication client
  • Easily switch themes/personas directly in the Customizing mode
  • Built-in support for H264 (MP4) on Mac OS X Snow Leopard (10.6) and newer through native APIs
  • Wikipedia search now uses HTTPS for secure searching
  • Implementation of HTTP/2 (draft14) and ALPN
  • Recover from a locked Firefox process in the "Firefox is already running" dialog on Windows
  • ECMAScript 6 WeakSet Implemented
  • JavaScript Template Strings Implemented
  • CSS3 Font variants and features control (e.g. kerning) implemented
  • WebCrypto: RSA-OAEP, PBKDF2 and AES-KW support
  • WebCrypto: wrapKey and unwrapKey implemented
  • WebCrypto: Import/export of JWK-formatted keys
  • matches() DOM API implemented (formerly mozMatchesSelector())
  • Performance.now() for workers implemented
  • WebCrypto: ECDH support
  • Support for the ECMAScript 6 Symbol data type added
  • WebIDE: Create, edit, and test a new Web application from your browser
  • Highlight all nodes that match a given selector in the Style Editor and the Inspector's Rules panel
  • Improved User Interface of the Profiler
  • console.table function added to web console
  • CSS transitions start correctly when started at the same time as changes to display, position, overflow, and similar properties

New in version 34.0 Beta 7 (November 7th, 2014)

  • Firefox Hello real-time communication client
  • Easily switch themes/personas directly in the Customizing mode
  • Built-in support for H264 (MP4) on Mac OS X Snow Leopard (10.6) and newer through native APIs
  • Wikipedia search now uses HTTPS for secure searching
  • Implementation of HTTP/2 (draft14) and ALPN
  • Recover from a locked Firefox process in the "Firefox is already running" dialog on Windows
  • ECMAScript 6 WeakSet Implemented
  • JavaScript Template Strings Implemented
  • CSS3 Font variants and features control (e.g. kerning) implemented
  • WebCrypto: RSA-OAEP, PBKDF2 and AES-KW support
  • WebCrypto: wrapKey and unwrapKey implemented
  • WebCrypto: Import/export of JWK-formatted keys
  • matches() DOM API implemented (formerly mozMatchesSelector())
  • Performance.now() for workers implemented
  • WebCrypto: ECDH support
  • Support for the ECMAScript 6 Symbol data type added
  • WebIDE: Create, edit, and test a new Web application from your browser
  • Highlight all nodes that match a given selector in the Style Editor and the Inspector's Rules panel
  • Improved User Interface of the Profiler
  • console.table function added to web console
  • CSS transitions start correctly when started at the same time as changes to display, position, overflow, and similar properties

New in version 33.0.3 (November 7th, 2014)

  • Blacklisted graphics drivers that were causing black screens with OMTC enabled (see bug 1093863)

New in version 34.0 Beta 6 (November 4th, 2014)

  • Firefox Hello real-time communication client
  • Easily switch themes/personas directly in the Customizing mode
  • Built-in support for H264 (MP4) on Mac OS X Snow Leopard (10.6) and newer through native APIs
  • Wikipedia search now uses HTTPS for secure searching
  • Non-intrusive way to set Firefox as default browser
  • Implementation of HTTP/2 (draft14) and ALPN
  • Recover from a locked Firefox process in the "Firefox is already running" dialog on Windows
  • ECMAScript 6 WeakSet Implemented
  • JavaScript Template Strings Implemented
  • CSS3 Font variants and features control (e.g. kerning) implemented
  • WebCrypto: RSA-OAEP, PBKDF2 and AES-KW support
  • WebCrypto: wrapKey and unwrapKey implemented
  • WebCrypto: Import/export of JWK-formatted keys
  • matches() DOM API implemented (formerly mozMatchesSelector())
  • Performance.now() for workers implemented
  • WebCrypto: ECDH support
  • Support for the ECMAScript 6 Symbol data type added
  • WebIDE: Create, edit, and test a new Web application from your browser
  • Highlight all nodes that match a given selector in the Style Editor and the Inspector's Rules panel
  • Improved User Interface of the Profiler
  • console.table function added to web console
  • CSS transitions start correctly when started at the same time as changes to display, position, overflow, and similar properties

New in version 34.0 Beta 5 (November 1st, 2014)

  • Firefox Hello real-time communication client
  • Easily switch themes/personas directly in the Customizing mode
  • Built-in support for H264 (MP4) on Mac OS X Snow Leopard (10.6) and newer through native APIs
  • Wikipedia search now uses HTTPS for secure searching
  • Non-intrusive way to set Firefox as default browser
  • Implementation of HTTP/2 (draft14) and ALPN
  • Recover from a locked Firefox process in the "Firefox is already running" dialog on Windows
  • ECMAScript 6 WeakSet Implemented
  • JavaScript Template Strings Implemented
  • CSS3 Font variants and features control (e.g. kerning) implemented
  • WebCrypto: RSA-OAEP, PBKDF2 and AES-KW support
  • WebCrypto: wrapKey and unwrapKey implemented
  • WebCrypto: Import/export of JWK-formatted keys
  • matches() DOM API implemented (formerly mozMatchesSelector())
  • Performance.now() for workers implemented
  • WebCrypto: ECDH support
  • Support for the ECMAScript 6 Symbol data type added
  • WebIDE: Create, edit, and test a new Web application from your browser
  • Highlight all nodes that match a given selector in the Style Editor and the Inspector's Rules panel
  • Improved User Interface of the Profiler
  • console.table function added to web console
  • CSS transitions start correctly when started at the same time as changes to display, position, overflow, and similar properties

New in version 33.0.2 (October 28th, 2014)

  • Fix a startup crash with some combination of hardware and drivers.

New in version 34.0 Beta 4 (October 28th, 2014)

  • Firefox Hello real-time communication client
  • Easily switch themes/personas directly in the Customizing mode
  • Built-in support for H264 (MP4) on Mac OS X Snow Leopard (10.6) and newer through native APIs
  • Wikipedia search now uses HTTPS for secure searching
  • Non-intrusive way to set Firefox as default browser
  • Implementation of HTTP/2 (draft14) and ALPN
  • Recover from a locked Firefox process in the "Firefox is already running" dialog on Windows
  • ECMAScript 6 WeakSet Implemented
  • JavaScript Template Strings Implemented
  • CSS3 Font variants and features control (e.g. kerning) implemented
  • WebCrypto: RSA-OAEP, PBKDF2 and AES-KW support
  • WebCrypto: wrapKey and unwrapKey implemented
  • WebCrypto: Import/export of JWK-formatted keys
  • matches() DOM API implemented (formerly mozMatchesSelector())
  • Performance.now() for workers implemented
  • WebCrypto: ECDH support
  • Support for the ECMAScript 6 Symbol data type added
  • WebIDE: Create, edit, and test a new Web application from your browser
  • Highlight all nodes that match a given selector in the Style Editor and the Inspector's Rules panel
  • Improved User Interface of the Profiler
  • console.table function added to web console
  • CSS transitions start correctly when started at the same time as changes to display, position, overflow, and similar properties

New in version 33.0.1 (October 24th, 2014)

  • Firefox displays a black screen at start-up with certain graphics drivers

New in version 34.0 Beta 3 (October 24th, 2014)

  • Firefox Hello real-time communication client
  • Easily switch themes/personas directly in the Customizing mode
  • Built-in support for H264 (MP4) on Mac OS X Snow Leopard (10.6) and newer through native APIs
  • Wikipedia search now uses HTTPS for secure searching
  • Non-intrusive way to set Firefox as default browser
  • Implementation of HTTP/2 (draft14) and ALPN
  • Recover from a locked Firefox process in the "Firefox is already running" dialog on Windows
  • ECMAScript 6 WeakSet Implemented
  • JavaScript Template Strings Implemented
  • CSS3 Font variants and features control (e.g. kerning) implemented
  • WebCrypto: RSA-OAEP, PBKDF2 and AES-KW support
  • WebCrypto: wrapKey and unwrapKey implemented
  • WebCrypto: Import/export of JWK-formatted keys
  • matches() DOM API implemented (formerly mozMatchesSelector())
  • Performance.now() for workers implemented
  • WebCrypto: ECDH support
  • Support for the ECMAScript 6 Symbol data type added
  • WebIDE: Create, edit, and test a new Web application from your browser
  • Highlight all nodes that match a given selector in the Style Editor and the Inspector's Rules panel
  • Improved User Interface of the Profiler
  • console.table function added to web console
  • CSS transitions start correctly when started at the same time as changes to display, position, overflow, and similar properties

New in version 34.0 Beta 1 (October 17th, 2014)

  • Firefox Hello real-time communication client
  • Easily switch themes/personas directly in the Customizing mode
  • Built-in support for H264 (MP4) on Mac OS X Leopard (10.6) and newer through native APIs
  • Wikipedia search now uses HTTPS for secure searching
  • Non-intrusive way to set Firefox as default browser
  • Implementation of HTTP/2 (draft14) and ALPN
  • Recover from a locked Firefox process in the "Firefox is already running" dialog on Windows
  • ECMAScript 6 WeakSet Implemented
  • JavaScript Template Strings Implemented
  • CSS3 Font variants and features control (e.g. kerning) implemented
  • WebCrypto: RSA-OAEP, PBKDF2 and AES-KW support
  • WebCrypto: wrapKey and unwrapKey implemented
  • WebCrypto: Import/export of JWK-formatted keys
  • matches() DOM API implemented (formerly mozMatchesSelector())
  • Performance.now() for workers implemented
  • WebCrypto: ECDH support
  • Support for the ECMAScript 6 Symbol data type added
  • WebIDE: Create, edit, and test a new Web application from your browser
  • Highlight all nodes that match a given selector in the Style Editor and the Inspector's Rules panel
  • Improved User Interface of the Profiler
  • console.table function added to web console
  • CSS transitions start correctly when started at the same time as changes to display, position, overflow, and similar properties

New in version 33.0 (October 14th, 2014)

  • Windows: OMTC enabled by default
  • OpenH264 support (sandboxed)
  • Enhanced Tiles
  • Continued experimentation with WebRTC-powered communications feature
  • Improved search experience through the location bar
  • Slimmer and faster JavaScript strings
  • Search suggestions on the Firefox Start (about:home) and new tab (about:newtab) pages
  • New CSP (Content Security Policy) backend
  • Support for connecting to HTTP proxy over HTTPS
  • Improved reliability of the session restoration
  • Azerbaijani [az] locale added
  • Proprietary window.crypto properties/functions removed
  • JSD (JavaScript Debugger Service) removed in favor of the Debugger interface
  • DOMMatrix interface implemented
  • @counter-style rule from CSS3 Counter Styles specification implemented
  • WebCrypto: RSA-OAEP, PBKDF2 and AES-KW support
  • WebCrypto: wrapKey and unwrapKey implemented
  • WebCrypto: Import/export of JWK-formatted keys
  • Cubic-bezier curves editor
  • Display which elements have listeners attached
  • New sidebar which displays a list of shortcuts to every @media rule in the current stylesheet
  • Paint flashing for browser content repaints
  • Editable @keyframes rules in the Rules section of the Inspector
  • CSS transform highlighter in the style-inspector

New in version 33.0 Beta 8 (October 1st, 2014)

  • Enhanced Tiles
  • Continued experimentation with WebRTC-powered communications feature
  • OpenH264 support (sandboxed)
  • Slimmer and faster JavaScript strings (learn more)
  • Improved reliability of the session restoration (learn more)
  • New CSP (Content Security Policy) backend
  • Improved search experience through the location bar
  • Connect to HTTP proxy over HTTPS
  • Search suggestions on the Firefox Start Page (about:home)
  • Azerbaijani [az] locale added
  • JSD (JavaScript Debugger Service) removed in favor of the Debugger interface (learn more)
  • Proprietary window.crypto properties/functions removed
  • DOMMatrix interface implemented
  • @counter-style rule from CSS3 Counter Styles specification implemented
  • WebCrypto: wrapKey and unwrapKey implemented
  • WebCrypto: Import/export of JWK-formatted keys
  • WebCrypto: RSA-OAEP, PBKDF2 and AES-KW support
  • Developer tools: Paint flashing for browser content repaints
  • Cubic-bezier curves editor
  • Display which elements have listeners attached
  • New sidebar which displays a list of shortcuts to every @media rule in the current stylesheet
  • Editable @keyframes rules in the Rules section of the Inspector
  • CSS transform highlighter to the style-inspector

New in version 32.0.3 (September 25th, 2014)

  • Security fixes

New in version 33.0 Beta 6 (September 23rd, 2014)

  • Enhanced Tiles
  • Continued experimentation with WebRTC-powered communications feature
  • OpenH264 support (sandboxed)
  • Slimmer and faster JavaScript strings (learn more)
  • Improved reliability of the session restoration (learn more)
  • New CSP (Content Security Policy) backend
  • Improved search experience through the location bar
  • Connect to HTTP proxy over HTTPS
  • Search suggestions on the Firefox Start Page (about:home)
  • Azerbaijani [az] locale added
  • JSD (JavaScript Debugger Service) removed in favor of the Debugger interface (learn more)
  • Proprietary window.crypto properties/functions removed
  • DOMMatrix interface implemented
  • @counter-style rule from CSS3 Counter Styles specification implemented
  • WebCrypto: wrapKey and unwrapKey implemented
  • WebCrypto: Import/export of JWK-formatted keys
  • WebCrypto: RSA-OAEP, PBKDF2 and AES-KW support
  • Developer tools: Paint flashing for browser content repaints
  • Cubic-bezier curves editor
  • Display which elements have listeners attached
  • New sidebar which displays a list of shortcuts to every @media rule in the current stylesheet
  • Editable @keyframes rules in the Rules section of the Inspector
  • CSS transform highlighter to the style-inspector

New in version 33.0 Beta 5 (September 19th, 2014)

  • Enhanced Tiles
  • Continued experimentation with WebRTC-powered communications feature
  • OpenH264 support (sandboxed)
  • Slimmer and faster JavaScript strings (learn more)
  • Improved reliability of the session restoration (learn more)
  • New CSP (Content Security Policy) backend
  • Improved search experience through the location bar
  • Connect to HTTP proxy over HTTPS
  • Search suggestions on the Firefox Start Page (about:home)
  • Azerbaijani [az] locale added
  • JSD (JavaScript Debugger Service) removed in favor of the Debugger interface (learn more)
  • Proprietary window.crypto properties/functions removed
  • DOMMatrix interface implemented
  • @counter-style rule from CSS3 Counter Styles specification implemented
  • WebCrypto: wrapKey and unwrapKey implemented
  • WebCrypto: Import/export of JWK-formatted keys
  • WebCrypto: RSA-OAEP, PBKDF2 and AES-KW support
  • Developer tools: Paint flashing for browser content repaints
  • Cubic-bezier curves editor
  • Display which elements have listeners attached
  • New sidebar which displays a list of shortcuts to every @media rule in the current stylesheet
  • Editable @keyframes rules in the Rules section of the Inspector
  • CSS transform highlighter to the style-inspector

New in version 33.0 Beta 4 (September 16th, 2014)

  • Enhanced Tiles
  • Continued experimentation with WebRTC-powered communications feature
  • OpenH264 support (sandboxed)
  • Slimmer and faster JavaScript strings (learn more)
  • Improved reliability of the session restoration (learn more)
  • New CSP (Content Security Policy) backend
  • Improved search experience through the location bar
  • Connect to HTTP proxy over HTTPS
  • Search suggestions on the Firefox Start Page (about:home)
  • Azerbaijani [az] locale added
  • JSD (JavaScript Debugger Service) removed in favor of the Debugger interface (learn more)
  • Proprietary window.crypto properties/functions removed
  • DOMMatrix interface implemented
  • @counter-style rule from CSS3 Counter Styles specification implemented
  • WebCrypto: wrapKey and unwrapKey implemented
  • WebCrypto: Import/export of JWK-formatted keys
  • WebCrypto: RSA-OAEP, PBKDF2 and AES-KW support
  • Developer tools: Paint flashing for browser content repaints
  • Cubic-bezier curves editor
  • Display which elements have listeners attached
  • New sidebar which displays a list of shortcuts to every @media rule in the current stylesheet
  • Editable @keyframes rules in the Rules section of the Inspector
  • CSS transform highlighter to the style-inspector

New in version 32.0.1 (September 13th, 2014)

  • Stability issues for computers with multiple graphics cards
  • Mixed content icon may be incorrectly displayed instead of lock icon for SSL sites
  • WebRTC: setRemoteDescription() silently fails if no success callback is specified

New in version 33.0 Beta 3 (September 12th, 2014)

  • Enhanced Tiles
  • Continued experimentation with WebRTC-powered communications feature
  • OpenH264 support (sandboxed)
  • Slimmer and faster JavaScript strings (learn more)
  • Improved reliability of the session restoration (learn more)
  • New CSP (Content Security Policy) backend
  • Improved search experience through the location bar
  • Connect to HTTP proxy over HTTPS
  • Search suggestions on the Firefox Start Page (about:home)
  • Azerbaijani [az] locale added
  • JSD (JavaScript Debugger Service) removed in favor of the Debugger interface (learn more)
  • Proprietary window.crypto properties/functions removed
  • DOMMatrix interface implemented
  • @counter-style rule from CSS3 Counter Styles specification implemented
  • WebCrypto: wrapKey and unwrapKey implemented
  • WebCrypto: Import/export of JWK-formatted keys
  • WebCrypto: RSA-OAEP, PBKDF2 and AES-KW support
  • Developer tools: Paint flashing for browser content repaints
  • Cubic-bezier curves editor
  • Display which elements have listeners attached
  • New sidebar which displays a list of shortcuts to every @media rule in the current stylesheet
  • Editable @keyframes rules in the Rules section of the Inspector
  • CSS transform highlighter to the style-inspector

New in version 33.0 Beta 2 (September 9th, 2014)

  • Enhanced Tiles
  • Continued experimentation with WebRTC-powered communications feature
  • OpenH264 support (sandboxed)
  • Slimmer and faster JavaScript strings (learn more)
  • Improved reliability of the session restoration (learn more)
  • New CSP (Content Security Policy) backend
  • Improved search experience through the location bar
  • Connect to HTTP proxy over HTTPS
  • Search suggestions on the Firefox Start Page (about:home)
  • Azerbaijani [az] locale added
  • JSD (JavaScript Debugger Service) removed in favor of the Debugger interface (learn more)
  • Proprietary window.crypto properties/functions removed
  • DOMMatrix interface implemented
  • @counter-style rule from CSS3 Counter Styles specification implemented
  • WebCrypto: wrapKey and unwrapKey implemented
  • WebCrypto: Import/export of JWK-formatted keys
  • WebCrypto: RSA-OAEP, PBKDF2 and AES-KW support
  • Developer tools: Paint flashing for browser content repaints
  • Cubic-bezier curves editor
  • Display which elements have listeners attached
  • New sidebar which displays a list of shortcuts to every @media rule in the current stylesheet
  • Editable @keyframes rules in the Rules section of the Inspector
  • CSS transform highlighter to the style-inspector

New in version 32.0 (September 1st, 2014)

  • New HTTP caching (v2) enabled by default (learn more)
  • Integration of generational garbage collection
  • Public key pinning support enabled (learn more)
  • Login metadata viewable in password manager
  • Display the number of found items in the find toolbar
  • Code completion and inline documentation added to Scratchpad (learn more)
  • Connect to HTTP proxy over HTTPS
  • Removed and turned off trust bit for some 1024-bit root certificates
  • Performance improvements to Password Manager and Add-on Manager
  • drawFocusIfNeeded enabled by default
  • ECMAScript 6 built-in method Array#copyWithin implemented (docs)
  • CSS position:sticky enabled by default
  • mix-blend-mode enabled by default
  • New Array built-in: Array.from() (learn more)
  • navigator.languages property and languagechange event implemented (learn more)
  • Vibration API updated to latest W3C spec
  • CSS box-decoration-break replaces -moz-background-inline-policy (learn more)
  • HiDPI support in Developer Tools UI
  • Inspector button moved to the top left
  • Hidden nodes displayed differently in the markup-view
  • New Web Audio Editor (learn more)
  • Mac OS X: cmd-L does not open a new window when no window is available
  • Text Rendering Issues on Windows 7 with Platform Update KB2670838 (MSIE 10 Prerequisite) or on Windows 8.1

New in version 32.0 Beta 2 (July 29th, 2014)

  • New HTTP caching (v2) enabled by default (learn more)
  • Integration of generational garbage collection
  • Public key pinning support enabled (learn more)
  • Login metadata viewable in password manager
  • Display the number of found items in the find toolbar
  • Code completion and inline documentation added to Scratchpad (learn more)
  • Connect to HTTP proxy over HTTPS
  • Performance improvements to Password Manager and Add-on Manager
  • Removed and turned off trust bit for some 1024-bit root certificates
  • Vibration API updated to latest W3C spec
  • CSS box-decoration-break replaces -moz-background-inline-policy (learn more)
  • ECMAScript 6 built-in method Array#copyWithin implemented (docs)
  • CSS position:sticky enabled by default
  • drawFocusIfNeeded enabled by default
  • mix-blend-mode enabled by default
  • New Array built-in: Array.from() (learn more)
  • navigator.languages property and languagechange event implemented (learn more)
  • HiDPI support in Developer Tools UI
  • Inspector button moved to the top left
  • New Web Audio Editor (learn more)
  • Hidden nodes displayed differently in the markup-view
  • Mac OS X: cmd-L does not open a new window when no window is available
  • Text Rendering Issues on Windows 7 with Platform Update KB2670838 (MSIE 10 Prerequisite) or on Windows 8.1

New in version 32 Beta 1 (July 28th, 2014)

  • New HTTP caching (v2) enabled by default (learn more)
  • Integration of generational garbage collection
  • Public key pinning support enabled (learn more)
  • Login metadata viewable in password manager
  • Display the number of found items in the find toolbar
  • Code completion and inline documentation added to Scratchpad (learn more)
  • Connect to HTTP proxy over HTTPS
  • Performance improvements to Password Manager and Add-on Manager
  • Removed and turned off trust bit for some 1024-bit root certificates
  • Vibration API updated to latest W3C spec
  • CSS box-decoration-break replaces -moz-background-inline-policy (learn more)
  • ECMAScript 6 built-in method Array#copyWithin implemented (docs)
  • CSS position:sticky enabled by default
  • drawFocusIfNeeded enabled by default
  • mix-blend-mode enabled by default
  • New Array built-in: Array.from() (learn more)
  • navigator.languages property and languagechange event implemented (learn more)
  • HiDPI support in Developer Tools UI
  • Inspector button moved to the top left
  • New Web Audio Editor (learn more)
  • Hidden nodes displayed differently in the markup-view
  • Mac OS X: cmd-L does not open a new window when no window is available
  • Text Rendering Issues on Windows 7 with Platform Update KB2670838 (MSIE 10 Prerequisite) or on Windows 8.1

New in version 31.0 (July 21st, 2014)

  • Add the search field to the new tab page
  • mozilla::pkix as default certificate verifier (learn more)
  • OdinMonkey: Use backtracking allocator for asm.js style code
  • Integration of generational garbage collection
  • Partial implementation of the OpenType MATH table (section 6.3.6) see documentation about mathematical fonts and the MathML Torture Test for details
  • audio/video .ogg and .pdf files handled by Firefox if no application specified (Windows only)
  • Removal of the CAPS infrastructure for specifying site-specific permissions (via capability.policy.* preferences). Most notably, attempts to use this functionality to grant access to the clipboard will no longer work. The sole exception is the checkloaduri permission, which may still be used as before to allow sites to load file:// URIs.
  • WebVTT implemented and enabled (learn more)
  • CSS3 variables implemented (learn more)
  • Developer Tools: Add-on Debugger (learn more)
  • Developer Tools: Canvas Debugger (learn more)
  • New Array built-in: Array.prototype.fill() (learn more)
  • New Object built-in: Object.setPrototypeOf() (learn more)
  • CSP 1.1 nonce-source and hash-source enabled by default
  • Developer Tools: Eyedropper tool added to the color picker (learn more)
  • Developer Tools: Editable Box Model (learn more)
  • Developer Tools: Code Editor improvements (learn more)
  • Developer Tools: Console stack traces (learn more)
  • Developer Tools: Copy as cURL (learn more)
  • Developer Tools: Styled console logs (learn more)
  • navigator.sendBeacon enabled by default (learn more)
  • Dialogs spawned from the onbeforeunload event no longer block access to the rest of the browser
  • Search for partially selected link text from context menu (985824)

New in version 30.0 (June 10th, 2014)

  • Sidebars button in browser chrome enables faster access to social, bookmark, & history sidebars
  • Support for GStreamer 1.0
  • Mac OS X command-E sets find term to selected text
  • Disallow calling WebIDL constructors as functions on the web
  • With the exception of those bundled inside an extension or ones that are whitelisted, plugins will no longer be activated by default (see blog post)
  • Fixes to box-shadow and other visual overflow (see bug 480888)
  • Mute and volume available per window when using WebAudio
  • background-blend-mode enabled by default
  • Use of line-height allowed for ES6 array and generator comprehensions implemented (read docs for more details)
  • Error stack now contains column number
  • Support for alpha option in canvas context options (feature description)
  • Ignore autocomplete="off" when offering to save passwords via the password manager (see 956906)
  • TypedArrays don't support new named properties (see 695438)
  • Various security fixes

New in version 30.0 RC1 (June 4th, 2014)

  • Bug 1003707 - Retain size information for similar surfaces if we can.
  • Bug 985867 - Fix touch/click ordering on about:addons page.
  • Bug 995310 - Only create metro folder in metro environment.
  • Bug 993768. Patch is sort of a tag-team effort from jwalden and jonco.
  • Bug 998785 - Don't throw error for regexps Yarr bails on.
  • Bug 1015636 - Check if PDF Viewer embed overlay has valid state.
  • Bug 997406 - Take into account padding when deciding whether to show Share icon.
  • Bug 1007223 - Follow-up: Fix the media decoding test, and also ensure that we're freeing the right buffer.
  • Bug 1013972 - Make nsJSObjectWrapper::mJSObj a PersistentRooted.

New in version 29.0 (April 28th, 2014)

  • A set of new improvements to the Firefox user interface (learn more).
  • An interactive onboarding tour to guide users through new interface changes
  • A redesigned and improved customization mode
  • The ability to set up Firefox Sync by creating a Firefox account (learn more)
  • Gamepad API finalized and enabled (learn more)
  • Malay [ma] locale added
  • navigator.plugins is no longer enumerable, for user privacy
  • Clicking on a W3C Web Notification will switch to the originating tab
  • 'box-sizing' (dropping the -moz- prefix) implemented (learn more)
  • Console object available in Web Workers (learn more)
  • Promises enabled by default (learn more)
  • SharedWorker enabled by default
  • implemented and enabled
  • implemented and enabled
  • Enabled ECMAScript Internationalization API
  • Add-on bar has been removed, content moved to navigation bar

New in version 29.0 Beta 5 (April 4th, 2014)

  • Fixed bugs:
  • Bug 912627 - Remove spurious assertion.
  • Bug 990202 - Move the test page to a new window to prevent it from navigating the test runner frame back.
  • Bug 968129 - Load initial tab in WebappImpl:loadStartupTab.
  • Bug 989965 - Resolve style for pseudo-elements correctly when style rules that have user action pseudo-classes on them are present.
  • Bug 970213 - Replace icon with custom design.
  • Bug 919208 - Rewrite test_bug668513.html to run in its own window so that it won't be able to navigate the test runner frame back.
  • Bug 984447 - Properly handle forks in mozjemalloc after bug 694896.
  • Bug 983448 - Fix masm.convertUInt32ToFloat32 on x86.
  • Bug 989130 - Back out changeset fe119a83b1f2 (bug 942017) while leaving the corresponding test from changeset 3c63decb4e7e.
  • Bug 982448 - some fxmetro pref's still being left behind with values without --enable-metro in the mozconfig.
  • Bug 989586 - Fix Ion correctness bug when inlining |new Array(x)|.
  • Bug 989210 - Consistently make cycle collector to deal with TextTrackManager's member variables.
  • Bug 973264 - If we wrap gfxImageSurface data when creating a SourceSurface, hold a reference to the original surface so the data stays alive.
  • Bug 972844 - Add a Maybe Later link on about:feedback intro.
  • Bug 970209 - Surround update logic in about:apps with synth apk specific wrapper.
  • Bug 947531 - Focus the test window before starting the test.
  • Bug 965362 - Do not assume that all of the contents of the HTTP channel will be available by the time we decide to read it synchronously in devtools tests.
  • Bug 989183 - Check for nsXBLJSClass.

New in version 29.0 Beta 2 (March 25th, 2014)

  • A set of new improvements to the Firefox user interface (learn more)
  • An interactive onboarding tour to guide users through new changes
  • A redesigned and improved customization mode
  • The ability to set up Firefox Sync by creating a Firefox account (learn more)
  • Gamepad API finalized and enabled (learn more)
  • navigator.plugins is no longer enumerable, for user privacy
  • 'box-sizing' (dropping the -moz- prefix) implemented
  • SharedWorker enabled by default
  • CSS3 variables implemented
  • enabled
  • implemented and enabled
  • Promises enabled by default
  • Console object available in Web Workers
  • Add-on bar has been removed, content moved to navigation bar
  • Enabled ECMAScript Internationalization API
  • Echo cancellation on apprtc.appspot.com fails (974537)

New in version 28.0 (March 18th, 2014)

  • Firefox for Windows 8 touch preview available (see blog post)
  • Gamepad API finalized and enabled (learn more)
  • Mac OS X: Notification Center support for web notifications
  • Volume control for HTML5 audio/video
  • Support for Opus in WebM
  • VP9 video decoding implemented
  • Removed support for spdy/2
  • Support for MathML 2.0 'mathvariant' attribute
  • Background thread hang reporting
  • implemented and enabled
  • Support for multi-line flexbox in layout

New in version 28 Beta 4 (February 19th, 2014)

  • Firefox for Windows 8 touch preview available
  • Gamepad API finalized and enabled
  • Mac OS X: Notification Center support for web notifications
  • Volume control for HTML5 audio/video
  • Support for Opus in WebM
  • VP9 video decoding implemented
  • Removed support for spdy/2
  • Support for MathML 2.0 'mathvariant' attribute
  • Background thread hang reporting
  • implemented and enabled
  • Support for multi-line flexbox in layout

New in version 27.0.1 (February 14th, 2014)

  • Fixed stability issues with Greasemonkey and other JS that used ClearTimeoutOrInterval
  • JS math correctness issue (bug 941381)

New in version 27.0 (February 4th, 2014)

  • You can now run more than one service at a time with Firefox SocialAPI, allowing you to receive notifications, chat and more from multiple integrated services
  • Implemented support for TLS 1.2 (RFC 5246)
  • Added support for SPDY 3.1 protocol
  • Ability to reset style sheets using 'all:unset'
  • You can now choose to deobfuscate javascript in the debugger (see 762761)
  • Added support for scrolled fieldsets (see 261037)
  • Implemented allow-popups directive for iframe sandbox, enabling increased security (see 766282)
  • CSS cursor keywords -moz-grab and -moz-grabbing have been unprefixed (see 880672)
  • Added support for ES6 generators in SpiderMonkey (see blog post)
  • Implemented support for mathematical function Math.hypot() in ES6 (see 896264)
  • Dashed line support on Canvas (see 768067)
  • Get Azure/Skia content rendering working on Linux (see 740200)

New in version 26.0 (December 10th, 2013)

  • All plug-ins, with the exception of recent Flash plug-ins, are defaulted to 'click to play'
  • Password manager now supports script-generated password fields
  • Updates can now be performed by Windows users without write permissions to Firefox install directory (requires Mozilla Maintenance Service)
  • Support for H.264 on Linux if the appropriate gstreamer plug-ins are installed
  • Support for MP3 decoding on Windows XP, completing MP3 support across Windows OS versions
  • CSP implementation now supports multiple policies, including the case of both an enforced and Report-Only policy, per the spec
  • Social API now supports Social Bookmarking for multiple providers through its SocialMarks functionality (see MDN docs)
  • There is no longer a prompt when websites use appcache
  • Support for the CSS image orientation property
  • New App Manager allows you to deploy and debug HTML5 webapps on Firefox OS phones and the Firefox OS Simulator
  • IndexedDB can now be used as a "optimistic" storage area so it doesn't require any prompts and data is stored in a pool with LRU eviction policy, in short temporary storage
  • When displaying a standalone image, Firefox matches the EXIF orientation information contained within the JPEG image (298619)
  • Improved page load times due to no longer decoding images that aren't visible (847223)
  • AudioToolbox MP3 backend for OSX (914479)

New in version 25.0 (October 31st, 2013)

  • Web Audio support
  • The find bar is no longer shared between tabs
  • If away from Firefox for months, you now will be offered the option to reset it to its default state while preserving your essential information
  • Resetting Firefox no longer clears your browsing session
  • CSS3 background-attachment:local support to control background scrolling
  • Many new ES6 functions implemented
  • iframe document content can now be specified inline
  • Blank or missing page thumbnails when opening a new tab
  • Security fixes

New in version 24.0 (September 16th, 2013)

  • Support for new scrollbar style in Mac OS X 10.7 and newer
  • Implemented Close tabs to the right
  • Social: Ability to tear-off chat windows to view separately by simply dragging them out
  • Accessibility related improvements on using pinned tabs (see 577727)
  • Major SVG rendering improvements around Image tiling and scaling (see 600207)
  • Improved and unified Browser console for enhanced debugging experience, replacing existing Error console
  • Removed support for sherlock files that are loaded from application or profile directory
  • Support for W3C touch events disabled (see 888304)

New in version 24.0 Beta 2 (August 14th, 2013)

  • New:
  • Support for new scrollbar style in Mac OS X 10.7 and newer
  • Implemented Close tabs to the right
  • Social: Ability to tear-off chat windows to view separately by simply dragging them out
  • Changed:
  • Accessibility related improvements on using pinned tabs (see 577727)
  • Developer:
  • Major SVG rendering improvements around Image tiling and scaling (see 600207)
  • Improved and unified Browser console for enhanced debugging experience, replacing existing Error console
  • Removed support for sherlock files that are loaded from application or profile directory
  • HTML5:
  • Support for W3C touch events disabled (see 888304)

New in version 23.0 (August 6th, 2013)

  • Support for new scrollbar style in Mac OS X 10.7 and newer
  • Mixed content blocking enabled to protects users from man-in-the-middle attacks and eavesdroppers on HTTPS pages (learn more)
  • Improved about:memory's functional UI
  • Enabled DXVA2 on Windows Vista+ to accelerate H.264 video decoding
  • Updated Firefox Logo
  • "Load images automatically", "Enable JavaScript", and Always show the tab bar" checkboxes removed from preferences and reset to defaults
  • Simplified interface for notifications of plugin installation
  • Users can now switch to a new search provider across the entire browser
  • CSP policies using the standard syntax and semantics will now be enforced
  • Implemented a global browser console
  • Social share functionality
  • HTML5 form control implemented
  • Write more accessible pages on touch interfaces with new ARIA role for key buttons
  • Added unprefixed requestAnimationFrame
  • New feature in toolbox: Network Monitor
  • Dropped blink effect from text-decoration: blink; and completely removed element

New in version 22.0 (June 25th, 2013)

  • Windows: Firefox now follows display scaling options to render text larger on high-res displays
  • WebRTC is now enabled by default!
  • Mac OS X: Download progress in Dock application icon
  • HTML5 audio/video playback rate can now be changed
  • Social services management implemented in Add-ons Manager
  • asm.js optimizations (OdinMonkey) enabled for major performance improvements
  • Improved WebGL rendering performance through asynchronous canvas updates
  • Plain text files displayed within Firefox will now word-wrap
  • For user security, the |Components| object is no longer accessible from web content
  • Improved memory usage and display time when rendering images
  • Pointer Lock API can now be used outside of fullscreen
  • CSS3 Flexbox implemented and enabled by default
  • New Web Notifications API implemented
  • Added clipboardData API for JavaScript access to a user's clipboard
  • New built-in font inspector
  • New HTML5 and elements
  • Scrolling using some high-resolution-scroll aware touchpads feels slow (829952)

New in version 22.0 Beta 6 (June 18th, 2013)

  • WebRTC is now enabled by default!
  • HTML5 audio/video playback rate can now be changed
  • Social services management implemented in Add-ons Manager
  • asm.js optimizations (OdinMonkey) enabled for major performance improvements
  • Improved WebGL rendering performance through asynchronous canvas updates
  • Plain text files displayed within Firefox will now word-wrap
  • For user security, the |Components| object is no longer accessible from web content
  • Improved memory usage and display time when rendering images
  • Pointer Lock API can now be used outside of fullscreen
  • CSS3 Flexbox implemented and enabled by default
  • New Web Notifications API implemented
  • Added clipboardData API for JavaScript access to a user's clipboard
  • New built-in font inspector
  • New HTML5 and elements
  • Scrolling using some high-resolution-scroll aware touchpads feels slow (829952)

New in version 22.0 Beta 3 (May 29th, 2013)

  • Windows: Firefox now follows display scaling options to render text larger on high-res displays
  • WebRTC is now enabled by default!
  • Mac OS X: Download progress in Dock application icon
  • HTML5 audio/video playback rate can now be changed
  • Social services management implemented in Add-ons Manager
  • asm.js optimizations (OdinMonkey) enabled for major performance improvements
  • Improved WebGL rendering performance through asynchronous canvas updates
  • Plain text files displayed within Firefox will now word-wrap
  • For user security, the |Components| object is no longer accessible from web content
  • Improved memory usage and display time when rendering images
  • Pointer Lock API can now be used outside of fullscreen
  • CSS3 Flexbox implemented and enabled by default
  • New Web Notifications API implemented
  • Added clipboardData API for JavaScript access to a user's clipboard
  • New built-in font inspector
  • New HTML5 and elements
  • Scrolling using some high-resolution-scroll aware touchpads feels slow (829952)

New in version 22.0 Beta 2 (May 23rd, 2013)

  • Windows: Firefox now follows display scaling options to render text larger on high-res displays
  • WebRTC is now enabled by default!
  • Mac OS X: Download progress in Dock application icon
  • HTML5 audio/video playback rate can now be changed
  • Social services management implemented in Add-ons Manager
  • asm.js optimizations (OdinMonkey) enabled for major performance improvements
  • Improved WebGL rendering performance through asynchronous canvas updates
  • Plain text files displayed within Firefox will now word-wrap
  • For user security, the |Components| object is no longer accessible from web content
  • Improved memory usage and display time when rendering images
  • Pointer Lock API can now be used outside of fullscreen
  • CSS3 Flexbox implemented and enabled by default
  • New Web Notifications API implemented
  • Added clipboardData API for JavaScript access to a user's clipboard
  • New built-in font inspector
  • New HTML5 and elements
  • Scrolling using some high-resolution-scroll aware touchpads feels slow (829952)

New in version 22.0 Beta 1 (May 17th, 2013)

  • Windows: Firefox now follows display scaling options to render text larger on high-res displays
  • WebRTC is now enabled by default!
  • Mac OS X: Download progress in Dock application icon
  • HTML5 audio/video playback rate can now be changed
  • Social services management implemented in Add-ons Manager
  • asm.js optimizations (OdinMonkey) enabled for major performance improvements
  • Improved WebGL rendering performance through asynchronous canvas updates
  • Plain text files displayed within Firefox will now word-wrap
  • For user security, the |Components| object is no longer accessible from web content
  • Improved memory usage and display time when rendering images
  • Pointer Lock API can now be used outside of fullscreen
  • CSS3 Flexbox implemented and enabled by default
  • New Web Notifications API implemented
  • Added clipboardData API for JavaScript access to a user's clipboard
  • New built-in font inspector
  • New HTML5 and elements
  • Scrolling using some high-resolution-scroll aware touchpads feels slow (829952)

New in version 21.0 (May 14th, 2013)

  • Enhanced three-state UI for Do Not Track (DNT)
  • Firefox will suggest how to improve your application startup time if needed
  • Preliminary implementation of Firefox Health Report (see FAQ)
  • Ability to Restore removed thumbnails on New tab Page
  • Add-ons History API removals in Places
  • CSS -moz-user-select:none selection changed to improve compatibility with -webkit-user-select:none (bugs 816298)
  • Graphics related performance improvements (bugs 809821)
  • Removed E4X support from SpiderMonkey
  • Implemented Remote Profiling
  • Integrated, Add-on SDK loader and API libraries into Firefox
  • Added support for element
  • Implemented scoped stylesheets
  • Some function keys may not work when pressed (833719)
  • Browsing and Download history clearing needs unification to avoid confusion on clearing download history (847627)

New in version 22.0 Alpha 2 (April 9th, 2013)

  • Ability to only allow cookies from sites you've visited
  • HTML5 audio/video playback rate can now be changed
  • Improved WebGL rendering performance through asynchronous canvas updates
  • Improved memory usage and display time when rendering many images
  • Plain text files displayed within Firefox will now word-wrap
  • Pointer Lock API can now be used outside of fullscreen
  • New HTML5 , , and elements
  • New Web Notifications API implemented
  • New built-in font inspector
  • Added clipboardData API for JavaScript access to a user's clipboard
  • CSS3 Flexbox implemented and enabled by default

New in version 20.0 (April 2nd, 2013)

  • Per-window Private Browsing. Learn more.
  • New download experience. Learn more.
  • Ability to close hanging plugins, without the browser hanging
  • Continued performance improvements around common browser tasks (page loads, downloads, shutdown, etc.)
  • Continued implementation of draft ECMAScript 6 - clear() and Math.imul
  • New JavaScript Profiler tool
  • getUserMedia implemented for web access to the user's camera and microphone (with user permission)
  • now supports blend modes
  • Various and improvements
  • Details button on Crash Reporter (793972)
  • Unity plugin doesn't display in HiDPI mode (829284)

New in version 20.0 Beta 6 (March 21st, 2013)

  • Per-window Private Browsing
  • New download experience
  • Ability to close hanging plugins, without the browser hanging
  • Firefox will offer to reset the Awesomebar search provider, if it has been changed by third-party software or through about:config
  • Continued performance improvements around common browser tasks (page loads, downloads, shutdown, etc.)
  • Continued implementation of draft ECMAScript 6 - clear() and Math.imul
  • New JavaScript Profiler tool
  • now supports blend modes
  • Various and improvements
  • getUserMedia implemented for web access to the user's camera and microphone (with user permission)
  • Details button on Crash Reporter (793972)
  • Unity plugin doesn't display in HiDPI mode (829284)

New in version 20.0 Beta 1 (February 23rd, 2013)

  • Per-window Private Browsing
  • New download experience
  • Ability to close hanging plugins, without the browser hanging
  • Firefox will offer to reset the Awesomebar search provider, if it has been changed by third-party software or through about:config
  • Continued performance improvements around common browser tasks (page loads, downloads, shutdown, etc.)
  • Continued implementation of draft ECMAScript 6 - clear() and Math.imul
  • New JavaScript Profiler tool
  • now supports blend modes
  • Various and improvements
  • getUserMedia implemented for web access to the user's camera and microphone (with user permission)
  • Details button on Crash Reporter (793972)
  • Unity plugin doesn't display in HiDPI mode (829284)

New in version 19.0 (February 19th, 2013)

  • Built-in PDF viewer
  • Canvas elements can export their content as an image blob using canvas.toBlob()
  • Startup performance improvements (bugs 715402 and 756313)
  • Debugger now supports pausing on exceptions and hiding non-enumerable properties
  • Remote Web Console is available for connecting to Firefox on Android or Firefox OS (experimental, set devtools.debugger.remote-enabled to true)
  • There is now a Browser Debugger available for add-on and browser developers (experimental, set devtools.chrome.enabled to true)
  • Web Console CSS links now open in the Style Editor
  • CSS @page is now supported
  • CSS viewport-percentage length units implemented (vh, vw, vmin and vmax)
  • CSS text-transform now supports full-width
  • Starting Firefox with -private flag incorrectly claims you are not in Private Browsing mode (802274)

New in version 18.0.1 (January 19th, 2013)

  • Problems involving HTTP Proxy Transactions (Associated bugs)
  • Unity player crashes on Mac OS X (bug 828954)
  • Disabled HIDPI support on external monitors to avoid rendering glitches (bug 814434)

New in version 19.0 Beta 1 (January 11th, 2013)

  • Built-in PDF viewer
  • Firefox will offer to reset the Awesomebar search provider, if it has been changed by third-party software or through about:config
  • Canvas elements can export their content as an image blob using canvas.toBlob()
  • Startup performance improvements (bugs 715402 and 756313)
  • Debugger now supports pausing on exceptions and hiding non-enumerable properties
  • Remote Web Console is available for connecting to Firefox on Android or Firefox OS (experimental, set devtools.debugger.remote-enabled to true)
  • There is now a Browser Debugger available for add-on and browser developers (experimental, set devtools.chrome.enabled to true)
  • Web Console CSS links now open in the Style Editor
  • CSS @page is now supported
  • CSS viewport-percentage length units implemented (vh, vw, vmin and vmax)
  • CSS text-transform now supports full-width
  • Starting Firefox with -private flag incorrectly claims you are not in Private Browsing mode (802274)

New in version 18.0 (January 8th, 2013)

  • Faster JavaScript performance via IonMonkey compiler
  • Support for Retina Display on OS X 10.7 and up
  • Preliminary support for WebRTC
  • Experience better image quality with our new HTML scaling algorithm
  • Performance improvements around tab switching
  • Support for new DOM property window.devicePixelRatio
  • Improvement in startup time through smart handling of signed extension certificates
  • Support for W3C touch events implemented, taking the place of MozTouch events
  • Disable insecure content loading on HTTPS pages (62178)
  • Improved responsiveness for users on proxies (769764)

New in version 17.0 ESR (November 20th, 2012)

  • 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 (see blog post)
  • Mac OS X 10.8: Support for Notification Center
  • Updated Awesome Bar experience with larger icons
  • 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
  • Pointer lock doesn't work in web apps (769150)
  • Page scrolling on sites with fixed headers (780345)

New in version 16.0 (October 9th, 2012)

  • Firefox on Mac OS X now has preliminary VoiceOver support turned on by default
  • Initial web app support (Windows/Mac/Linux)
  • Acholi localization 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 in Firefox 16
  • Recently opened files list in Scratchpad implemented
  • Debugger breakpoints do not catch on page reload (783393)
  • No longer supporting MD5 as a hash algorithm in digital signatures (650355)
  • Opus support by default (772341)
  • Reverse animation direction has been implemented (655920)
  • Per tab reporting in about:memory (687724)
  • User Agent strings for pre-release Firefox versions now show only major version (728831)

New in version 15.0 (August 28th, 2012)

  • Preliminary native PDF support (Aurora/Beta only)
  • Support for SPDY networking protocol v3
  • WebGL enhancements, including compressed textures for better performance
  • Optimized memory usage for add-ons
  • JavaScript debugger integrated into developer tools
  • New layout view added to Inspector
  • The CSS word-break property has been implemented.
  • High precision event timer implemented
  • New responsive design tool allows web developers to switch between desktop and mobile views of sites
  • Native support for the Opus audio codec added
  • The element now supports the media attribute
  • The and elements now support the played attribute

New in version 14.0.1 (July 17th, 2012)

  • Google searches now utilize HTTPS
  • Plugins can now be configured to only load on click (requires an about:config change)
  • 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
  • CSS :hover regression when an element's class name is set by Javascript (758885)

New in version 13.0 (June 2nd, 2012)

  • 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

New in version 13 Beta 3 (May 11th, 2012)

  • 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

New in version 12.0 (April 22nd, 2012)

  • 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
  • The column-fill CSS property has been implemented
  • Support for the text-align-last CSS property has been added
  • Experimental support for ECMAScript 6 Map and Set objects has been implemented

New in version 12.0 Beta 1 (March 17th, 2012)

  • 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
  • The column-fill CSS property has been implemented
  • Support for the text-align-last CSS property has been added
  • Experimental support for ECMAScript 6 Map and Set objects has been implemented

New in version 11.0 (March 13th, 2012)

  • Firefox can now migrate your bookmarks, history, and cookies from Google Chrome
  • With Sync enabled, add-ons can now be synchronized across your computers
  • The CSS text-size-adjust property is now supported
  • The outerHTML property is now supported on HTML elements
  • View source syntax highlighting now uses the HTML5 parser (see bug 482921)
  • The Style Editor for CSS editing is now available to web developers
  • Web developers can now visualize a web page in 3D using the Page Inspector 3D View
  • SPDY protocol support for faster page loads is now testable
  • XMLHttpRequest now supports HTML parsing
  • Files can now be stored in IndexedDB (see bug 661877)
  • Websockets has now been unprefixed
  • Redesigned media controls for HTML5 video
  • Firefox notifications may not work properly with Growl 1.3 or later (691662)

New in version 11.0 Beta 1 (February 6th, 2012)

  • Firefox can now migrate your bookmarks, history, and cookies from Google Chrome
  • With Sync enabled, add-ons can now be synchronized across your computers
  • The CSS text-size-adjust property is now supported
  • The outerHTML property is now supported on HTML elements
  • View source syntax highlighting now uses the HTML5 parser (see bug 482921)
  • The Style Editor for CSS editing is now available to web developers
  • Web developers can now visualize a web page in 3D using the Page Inspector 3D View
  • SPDY protocol support for faster page loads is now testable
  • XMLHttpRequest now supports HTML parsing
  • Files can now be stored in IndexedDB (see bug 661877)
  • Websockets has now been unprefixed
  • Redesigned media controls for HTML5 video
  • Firefox notifications may not work properly with Growl 1.3 or later (691662)

New in version 11.0 Beta 1 (February 6th, 2012)

  • Tabs are now shown above the toolbar
  • New wizard to sign up for new accounts
  • More trust options added to junk settings (Bogofilter, DSPAM, POPFile)
  • and several other platform fixes

New in version 10.0 (January 31st, 2012)

  • The forward button is now hidden until you navigate back
  • Anti-Aliasing for WebGL is now implemented (see bug 615976)
  • Full Screen APIs allow you to build a web application that runs full screen (see the feature page)
  • CSS3 3D-Transforms are now supported (see bug 505115)
  • New < bdi > element for bi-directional text isolation, along with supporting CSS properties (see bugs 613149 and 662288)
  • Inspect tool with content highlighting, includes new CSS Style Inspector
  • We've added IndexedDB APIs to more closely match the specification
  • Some users may experience a crash when moving bookmarks (681795)

New in version 10.0 Beta 1 (December 23rd, 2011)

  • The forward button is now hidden until you navigate back
  • Anti-Aliasing for WebGL is now implemented (see bug 615976)
  • Full Screen APIs allow you to build a web application that runs full screen (see the feature page)
  • CSS3 3D-Transforms are now supported (see bug 505115)
  • New < bdi > element for bi-directional text isolation, along with supporting CSS properties (see bugs 613149 and 662288)
  • Inspect tool with content highlighting, includes new CSS Style Inspector
  • We've added IndexedDB APIs to more closely match the specification
  • Some users may experience a crash when moving bookmarks (681795)

New in version 8.0 (November 6th, 2011)

  • 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 tab animations when moving, reordering, or detaching tabs
  • Improved performance and memory handling when using and elements
  • Added 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

New in version 7.0 (September 27th, 2011)

  • Drastically improved memory use
  • 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
  • Added support for text-overflow: ellipsis
  • Added support for the Web Timing specification
  • Added an opt-in system for users to send performance data back to Mozilla to improve future versions of Firefox. This can be enabled by installing an add-on
  • Fixed several stability issues

New in version 6.0 Beta 1 (July 11th, 2011)

  • The address bar now highlights the domain of the website you're 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

New in version 4.0 RC2 (March 21st, 2011)

  • Blacklisted a few invalid HTTPS certificates
  • Updated localizations for 29 locales
  • Added Vietnamese localization, bringing the total languages available in Firefox 4 to 83

New in version 4.0 RC1 (March 10th, 2011)

  • General stability, performance, and compatibility improvements.

New in version 4.0 Beta 12 (February 28th, 2011)

  • Increased performance while viewing Flash content
  • Improved plugin compatibility with hardware acceleration enabled
  • Hovering over links now displays the URL at the bottom of the window rather than in the location bar
  • General stability, performance, and compatibility improvements

New in version 4.0 Beta 11 (February 8th, 2011)

  • Support for the proposed Do Not Track ("DNT") header
  • Connection status messages are now shown in a small overlay
  • WebGL has been re-enabled on Linux
  • The default homepage design has been refreshed
  • Firefox no longer switches into offline mode automatically

New in version 4.0 Beta 6 (September 15th, 2010)

  • Fixed a stability issue affecting Windows users.
  • Fixed an issue causing rendering errors with plugins
  • affecting Mac OS X users. See the complete changelist from the previous beta.
  • As well as these features from previous Firefox 4 Betas:
  • Firefox 4 Beta is available in 39 languages.
  • Support for the new proposed Audio Data API
  • Direct2D Hardware Acceleration is now on by default for Windows 7 users
  • Firefox button has a new look for Windows Vista and Windows 7 users
  • Support for HSTS security protocol allowing sites to insist that they only be loaded over SSL.
  • Firefox Sync is now included by default.
  • A new feature 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.
  • Tabs are now on top by default on Windows and OSX - Linux will be changing when the theme has been modified to support the change.
  • You can turn any tab into an "App Tab" by right-clicking on it and selecting "Make into App Tab" from the context menu.
  • Web developers can animate content using CSS Transitions.
  • Responsiveness and scrolling improvements from the new retained layers layout system.
  • JavaScript speed improvements due to engine optimizations.
  • Changes to how XPCOM components are registered in order to help startup time and process separation.
  • You can search for and switch to already open tabs in the Smart Location Bar.
  • New Addons Manager and extension management API (UI will be changed before final release).
  • Significant API improvements are available for JS-ctypes, a foreign function interface for extensions.
  • The stop and reload buttons have been merged into a single button on Windows, Mac 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 for Windows, Linux, and Mac when there is a crash in the Adobe Flash, Apple Quicktime or Microsoft Silverlight plugins.
  • CSS Transitions are partially supported.
  • Full WebGL support is included but disabled by default at this time.
  • Core Animation rendering model for plugins on Mac OS X. Plugins which also support this rendering model can now draw faster and more efficiently.
  • Native support for the HD HTML5 WebM video format.
  • An experimental Direct2D rendering backend is available on Windows, turned off by default.
  • Web developers can use Websockets for a low complexity, low latency, bidirectional communications API.
  • 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 (used for things like graphics and animations) more efficiently.

New in version 3.6.9 (September 8th, 2010)

  • Introduced support for the X-FRAME-OPTIONS HTTP response header. Site owners can use this to mitigate clickjacking attacks by ensuring that their content is not embedded into other sites.
  • Fixed several security issues.
  • Fixed several stability issues.

New in version 3.6.4 (June 22nd, 2010)

  • Firefox 3.6.4 provides uninterrupted browsing for Windows and Linux users when there is a crash in the Adobe Flash, Apple Quicktime or Microsoft Silverlight plugins.
  • If a plugin crashes or freezes, it will not affect the rest of Firefox. You will be able to reload the page to restart the plugin and try again.
  • Firefox 3.6.4 also fixes the following issues found in previous versions of Firefox 3.6:
  • Fixed several security issues.
  • Fixed several stability issues.

New in version 3.6.4 Beta Build 1 (April 21st, 2010)

  • Firefox 3.6.4 provides uninterrupted browsing for Windows and Linux users when there is a crash in the Adobe Flash, Apple Quicktime or Microsoft Silverlight plugins.
  • If a plugin crashes or freezes, it will not affect the rest of Firefox. You will be able to reload the page to restart the plugin and try again.
  • Firefox 3.6.4 also fixes the following issues found in previous versions of Firefox 3.6:
  • Fixed several security issues.
  • Fixed several stability issues.

New in version 3.6.3 (April 2nd, 2010)

  • Firefox 3.6.3 fixes a critical security issue that could potentially allow remote code execution (see bug 555109).
  • You may also be interested in the Firefox 3.6.2 release notes for a list of changes in the previous version.

New in version 3.6.2 (March 23rd, 2010)

  • Fixed a critical security issue that could potentially allow remote code execution (see bug 552216).
  • Fixed several additional security issues.
  • Fixed several stability issues.

New in version 3.7 Alpha 2 (March 3rd, 2010)

  • New Features and Changes:
  • Gecko 1.9.3 Alpha 2 introduces new features which can be tested by using this Mozilla Developer Preview. Many of these features are still in development, and while they will likely appear in some future version of Mozilla Firefox, some may be in earlier releases than others.
  • Plugins On Windows and Linux, plugins (such as Flash and Silverlight) are now isolated from Firefox. Plugin crashes will not kill Firefox itself, and unresponsive plugins are automatically restarted.
  • Security The SSL security system has been changed to fix a renegotiation flaw. For technical details, see the newsgroup posting announcing the change.
  • HTML The placeholder attribute for and is now supported.
  • User Interface The stop and reload buttons have been merged when they are adjacent on the toolbar. See bug 343396 for details.
  • SVG Support for SMIL Animation in SVG. Support for animating some SVG attributes is still under development and the animateMotion element isn't supported yet.
  • Stability Crash reports from plugin processes are now submitted automatically. Crash report submission can be disabled in Firefox preferences (Advanced / General / Submit crash reports).
  • CSS Support for CSS Transitions. This support is not quite complete: support for animation of transforms and gradients has not yet been implemented.
  • WebGL Support for WebGL, which is disabled by default but can be enabled by changing a preference. See this blog post and this blog post for more details.
  • DOM Support for the getClientRects and getBoundingClientRect methods on Range objects. See bug 396392 for details.
  • DOM Support for the setCapture and releaseCapture methods on DOM elements. See bug 503943 for details.
  • HTML Support for the HTML5 History.pushState() and History.replaceState() methods and the popstate event. See bug 500328 for details.
  • CSS Support for the -moz-image-rect() value for background-image. See bug 113577 for more details.

New in version 3.6 Beta 2 (November 11th, 2009)

  • More than 190 bug fixes from the last beta to improve performance, stability, security and features.
  • This beta is available in more than 45 languages - get your local version.
  • Users can now change their browser's appearance with a single click, with built in support for Personas.
  • Firefox 3.6 will alert users about out of date plugins to keep them safe.
  • Open, native video can now be displayed full screen, and supports poster frames.
  • Support for the WOFF font format.
  • Improved JavaScript performance, overall browser responsiveness and startup time.
  • Support for new CSS, DOM and HTML5 web technologies.

New in version 3.5.2 (August 3rd, 2009)

  • MFSA 2009-43 Heap overflow in certificate regexp parsing
  • MFSA 2009-42 Compromise of SSL-protected communication
  • MFSA 2009-38 Data corruption with SOCKS5 reply containing DNS name longer than 15 characters

New in version 3.5.2 Beta (August 3rd, 2009)

  • Several security and stability issues.
  • Images with ICC profiles now render properly on all monitors.

New in version 3.5.1 (July 17th, 2009)

  • Several security issues.
  • Several stability issues.
  • An issue that was making Firefox take a long time to load on some Windows systems.

New in version 3.0.10 (April 28th, 2009)

  • Fixed a security issue.
  • Fixed a major stability issue.

New in version 3.5 Beta 4 (April 28th, 2009)

  • Firefox 3.5 Beta 4 is based on the Gecko 1.9.1 rendering platform, which has been under development for the past 10 months. Firefox 3.5 offers many changes over the previous version, supporting new web technologies, improving performance and ease of use, and adding new features for users:
  • -This beta is now available in 70 languages - get your local version.
  • -Improved tools for controlling your private data, including a Private Browsing Mode.
  • -Better performance and stability with the new TraceMonkey JavaScript engine.
  • -The ability to provide Location Aware Browsing using web standards for geolocation.
  • -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: HTML5 and elements, downloadable fonts and other new CSS properties, JavaScript query selectors, HTML5 offline data storage for applications, and SVG transforms.

New in version 3.0.9 (April 21st, 2009)

  • Fixed several security issues.
  • Fixed several stability issues.
  • Many users experienced an issue where a corrupt local database caused Firefox to “lose” its stored cookies. (bug 470578)
  • Fixed an issue where, starting with Firefox 3.0.7, inline attachments on popular webmail services (like AOL and AIM) would not display. (bug 482659)
  • Large forms would sometimes take a long time to submit. (bug 426991)
  • In certain cases, new windows would not have proper focus. (bug 446568)

New in version 3.0.7 (March 5th, 2009)

  • Fixed several security issues.
  • Fixed several stability issues.
  • Official releases for the Estonian, Kannada and Telugu languages are now available.
  • Items in the "File" menu show as inactive after using the "Print" item from that menu - switching to a new tab restores them (bug 425844). This issue has been fixed.
  • For some users, cookies would appear to go “missing” after a few days (bug 444600).
  • Fixed several issues related to accessibility features.

New in version 3.0.4 (November 12th, 2008)

  • Fixed several security issues.
  • Fixed several stability issues.
  • Updated the internal Public Suffix list.
  • Fixed an issue where the IME input tool used to enter Japanese, Korean, Chinese and Indic characters was covered by the "Add Bookmark" panel. (bug 433340)
  • Enabled additional EV root certificates. (bug 451305)
  • Fixed an issue where some passwords saved using Firefox 3.0.2 did not work properly. (bug 457358)
  • In some cases, Firefox would not properly save proxy settings for protocols other than HTTP. (bug 446536)

New in version 3.0.1 (September 8th, 2008)

  • More Secure
  • One-click site info: Click the site favicon in the location bar to see who owns the site and to check if your connection is protected from eavesdropping. Identity verification is prominently displayed and easier to understand. When a site uses Extended Validation (EV) SSL certificates, the site favicon button will turn green and show the name of the company you're connected to. (Try it here!)
  • Malware Protection: malware protection warns users when they arrive at sites which are known to install viruses, spyware, trojans or other malware. (Try it here!)
  • New Web Forgery Protection page: the content of pages suspected as web forgeries is no longer shown. (Try it here!)
  • New SSL error pages: clearer and stricter error pages are used when Firefox encounters an invalid SSL certificate. (Try it here!)
  • Add-ons and Plugin version check: Firefox now automatically checks add-on and plugin versions and will disable older, insecure versions.
  • Secure add-on updates: to improve add-on update security, add-ons that provide updates in an insecure manner will be disabled.
  • Anti-virus integration: Firefox will inform anti-virus software when downloading executables.
  • Vista Parental Controls: Firefox now respects the Vista system-wide parental control setting for disabling file downloads.
  • 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 to Use
  • Easier password management: an information bar replaces the old password dialog so you can now save passwords after a successful login.
  • Simplified add-on installation: the add-ons whitelist has been removed making it possible to install extensions from third-party sites in fewer clicks.
  • New Download Manager: the revised download manager makes it much easier to locate downloaded files, and you can see and search on the name of the website where a file came from. Your active downloads and time remaining are always shown in the status bar as your files download.
  • Resumable downloading: users can now resume downloads after restarting the browser or resetting your network connection.
  • Full page zoom: from the View menu and via keyboard shortcuts, the new zooming feature lets you zoom in and out of entire pages, scaling the layout, text and images, or optionally only the text size. Your settings will be remembered whenever you return to the site.
  • Podcasts and Videocasts can be associated with your media playback tools.
  • Tab scrolling and quickmenu: tabs are easier to locate with the new tab scrolling and tab quickmenu.
  • Save what you were doing: Firefox will prompt users to save tabs on exit.
  • Optimized Open in Tabs behavior: opening a folder of bookmarks in tabs now appends the new tabs rather than overwriting.
  • Location and Search bar size can now be customized with a simple resizer item.
  • Text selection improvements: multiple text selections can be made with Ctrl/Cmd; double-click drag selects in "word-by-word" mode; triple-clicking selects a paragraph.
  • Find toolbar: the Find toolbar now opens with the current selection.
  • Plugin management: users can disable individual plugins in the Add-on Manager.
  • Integration with Windows: Firefox now has improved Windows icons, and uses native user interface widgets in the browser and in web forms.
  • Integration with the Mac: the new Firefox theme makes toolbars, icons, and other user interface elements look like a native OS X application. Firefox also uses OS X widgets and supports Growl for notifications of completed downloads and available updates. A combined back and forward control make it even easier to move between web pages.
  • Integration with Linux: Firefox's default icons, buttons, and menu styles now use the native GTK theme.
  • More Personal
  • Star button: quickly add bookmarks from the location bar with a single click; a second click lets you file and tag them.
  • Tags: associate keywords with your bookmarks to sort them by topic.
  • Location bar & auto-complete: type in all or part of the title, tag or address of a page to see a list of matches from your history and bookmarks; a new display makes it easier to scan through the matching results and find that page you're looking for. Results are returned according to their frecency (a combination of frequency and recency of visits to that page) ensuring that you're seeing the most relevant matches. An adaptive learning algorithm further tunes the results to your patterns!
  • Smart Bookmarks Folder: quickly access your recently bookmarked and tagged pages, as well as your more frequently visited pages with the new smart bookmarks folder on your bookmark toolbar.
  • Places Organizer: view, organize and search through all of your bookmarks, tags, and browsing history with multiple views and smart folders to store your frequent searches. Create and restore full backups whenever you want.
  • Web-based protocol handlers: web applications, such as your favorite webmail provider, can now be used instead of desktop applications for handling mailto: links from other sites. Similar support is available for other protocols (Web applications will have to first enable this by registering as handlers with Firefox).
  • Download & Install Add-ons: the Add-ons Manager (Tools > Add-ons) can now be used to download and install a Firefox customization from the thousands of Add-ons available from our community add-ons website. When you first open the Add-ons Manager, a list of recommended Add-ons is shown.
  • Easy to use Download Actions: a new Applications preferences pane provides a better UI for configuring handlers for various file types and protocol schemes.
  • Improved Platform for Developers
  • New graphics and font handling: new graphics and text rendering architectures in Gecko 1.9 provides rendering improvements in CSS, SVG as well as improved display of fonts with ligatures and complex scripts.
  • Color management: (set gfx.color_management.enabled on in about:config and restart the browser to enable.) Firefox can now adjust images with embedded color profiles.
  • Offline support: enables web applications to provide offline functionality (website authors must add support for offline browsing to their site for this feature to be available to users).
  • A more complete overview of Firefox 3 for developers is available for website and add-on developers.
  • Improved Performance
  • Speed: improvements to our JavaScript engine as well as profile guided optimizations have resulted in continued improvements in performance. Compared to Firefox 2, web applications like Google Mail and Zoho Office run twice as fast in Firefox 3, and the popular SunSpider test from Apple shows improvements over previous releases.
  • Memory usage: Several new technologies work together to reduce the amount of memory used by Firefox 3 over a web browsing session. Memory cycles are broken and collected by an automated cycle collector, a new memory allocator reduces fragmentation, hundreds of leaks have been fixed, and caching strategies have been tuned.
  • Reliability: A user's bookmarks, history, cookies, and preferences are now stored in a transactionally secure database format which will prevent data loss even if their system crashes.