Firefox 16 released with powerful developer tools

Mozilla has released version 16 of Firefox into the web browser's stable channel, and the most notable feature is the new Developer Toolbar and Command Line. The new Toolbar, when displayed, sits at the bottom of the browser window and devotes a large part of its real estate to the command line which is designed to provide quick, keyboard-driven access to many of the developer features in Firefox.

For example, the command "resize on" activates the responsive web testing mode, while "resize to 320 240" would activate it and set the size to 320 by 240. Some of the currently available commands are "inspect" for viewing nodes in the inspector, "cookie" to manipulate cookies, "console" to control the web console, "dbg" to control the the debugger, "restart" to restart the browser, "tilt" to get a 3D view of a page, and "addon" to enable or disable add-ons. The Toolbar also shows a visual indication of when messages have been sent to the console and buttons give quick access to the console, inspector and debugger. A Mozilla blog post discusses the Toolbar in detail and a video shows the Toolbar in action.

Mozilla demonstrates the power of the command line in Firefox 16

Firefox 16 also introduces initial support for chromeless web applications. Developers can use this functionality to build versions of their web sites that run in their own windows and resemble native applications. These apps are designed to be ready for distribution in Mozilla Marketplace, Mozilla's soon-to-launch HTML5/JavaScript app store which is expected to arrive alongside Firefox OS.

The developers have also improved JavaScript in Firefox by supporting incremental garbage collection which should smooth out the responsiveness of web applications running in the browser. CSS3 Animations, Transitions and Transforms have all had their -mozilla- prefixes removed as they are now stable CSS features. On Mac OS X, there is now preliminary support for Apple's built-in VoiceOver screen reader.

The mobile version of the browser on Android includes a new Reader Mode capability that presents what Mozilla calls "an enjoyable and clutter-free way to read online content" by reformatting web pages and removing advertisements. This optimises text-heavy web pages for smaller screens and makes them easier to read and can be activated by selecting the book icon next to the URL entry field.

Additionally, the mobile version of Firefox now supports more devices by introducing the ability to be run on the older ARMv6 processor architecture; previously the mobile browser only supported hardware with an ARMv7 CPU. A list of devices that have been tested and found to be compatible with the browser is provided on the Firefox Mobile site.

The mobile update also adds a new "Share" menu item that can send tabs to other devices over Firefox Sync. In addition, tel: URLs, which can wipe smartphones, will no longer be processed, but it is unclear whether this is blocking specific codes or all tel: URLs.

More details about both the desktop and mobile Firefox changes, including a list of fixes and known issues, can be found in the release notes. Firefox 16 is available to download for Windows, Mac OS X and Linux from the project's site. Firefox source code and binaries are released under the Mozilla Public Licence 2.0. Firefox for Android 16 is available from the Google Play store.

Update 12-10-12: Mozilla has now released version 16.0.1 of Firefox and Firefox for Android to close multiple vulnerabilities, including a privacy problem, discovered after the 16.0 release.

See also:

• Next Firefox ESR release planned, a report from The H.

(fab)