The new Web browser has revised and streamlined interface, some elements of which are already familiar to users of Google Chrome and Opera. Thus, the row of tabs at the top of the window, and access to the menu item opens a button Firefox in the upper left corner.

Firefox 4 has got a new manager additions, improved means of ensuring privacy, as well as support for an open video codec WebM, allowing an optimized view video directly in the browser and on all platforms. In addition, improved javascript engine and support for HTML 5.
 
In Firefox 4 Some plug-ins, namely Adobe Flash, Apple Quicktime and Microsoft Silverlight, performed in an isolated process. This means that the browser will continue to operate even in case of emergency shutdown plugin, and the user can try to re-open a web page when viewing the failure.
Mozilla today announced the availability of another, this time the fifth beta version of web browser Firefox 3.6.

The latest version includes several innovations, most of them are:

• support for HTML5 File API
• a new way to integrate third-party software to work with Firefox which aims to improve the safety (change)
• the possibility of asynchronous scripting in order to speed up page loading
• Built-in support for changes in the appearances of the browser with one click (Personas)
• Automatic outdated information on plugins
• Support for native full-screen video
• Support format fonts WOFF
• increased efficiency of javascript, shortened startup times and increased speed of the browser
• Improve technology support CSS, DOM, and HTML5

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