Firefox 21 full changelog

# NEW The Social API now supports multiple providers
# NEW Enhanced three-state UI for Do Not Track (DNT)
# NEW Firefox will suggest how to improve your application startup time if needed
# NEW Preliminary implementation of Firefox Health Report
# CHANGED Ability to restore removed thumbnails on New Tab Page
# CHANGED CSS -moz-user-select:none selection changed to improve compatibility with -webkit-user-select:none (bug 816298)
# CHANGED Graphics related performance improvements (bug 809821)
# CHANGED Removed E4X support from Spidermonkey
# DEVELOPER Implemented Remote Profiling
# DEVELOPER Integrated add-on SDK loader and API libraries into Firefox
# HTML5 Added support for <main> element
# HTML5 Implemented scoped stylesheets
# FIXED Some function keys may not work when pressed (833719)
# FIXED Browsing and Download history clearing needs unification to avoid confusion on clearing download history (847627)

* NEW Enhanced three-state UI for Do Not Track (DNT)
* NEW Firefox will suggest how to improve your application startup time if needed
* NEW Preliminary implementation of Firefox Health Report (see FAQ)
* CHANGED Ability to Restore removed thumbnails on New tab Page
* CHANGED Add-ons History API removals in Places
* CHANGED CSS -moz-user-select:none selection changed to improve compatibility with -webkit-user-select:none (bugs 816298)
* CHANGED Graphics related performance improvements (bugs 809821)
* CHANGED Removed E4X support from SpiderMonkey
* DEVELOPER Implemented Remote Profiling
* DEVELOPER Integrated, Add-on SDK loader and API libraries into Firefox
* HTML5 Added support for <main> element
* HTML5 Implemented scoped stylesheets
* FIXED Some function keys may not work when pressed (833719)

* NEW WebRTC enabled by default
* NEW Firefox will suggest how to improve your application startup time if needed
* NEW Enhanced three-state UI for DNT
* CHANGED Ability to Restore removed thumbnails on New tab Page
* CHANGED Graphics related performance improvements (bug 809821)
* CHANGED CSS -moz-user-select:none selection changed to improve compatibility with -webkit-user-select:none(bug 816298)
* CHANGED Add-ons History API removals in Places
* CHANGED Removed E4X support from Spidermonkey
* DEVELOPER Implemented Remote Profiling
* DEVELOPER Integrated, Add-on SDK loader and API libraries into Firefox
* HTML5 Added support for <main> element
* HTML5 Implemented scoped stylesheets
* FIXED Some function keys may not work when pressed (see 833719)
* Unresolved If you try to start Firefox using a locked profile, it will crash (see 573369)