Firefox 3.1 alpha 2, code-named Shiretoko, adds functionality for Web developers with very little eye candy for users.
Johnathan Nightingale of Mozilla described Firefox 3.1 as having more refinement than new features. This alpha release is intended for developers and testers only and should not yet be for general-purpose use.
The most visible enhancement in this alpha release is a feature that allows you to drag and drop tabs between two open Firefox browsers.
There are considerable under-the-hood enhancements here. Built on a pre-release version of the Gecko 1.9.1 rendering engine, Firefox 3.1 alpha 2 includes support for a video tag element in the HTML 5 standard, which allows designers to embed video directly into pages without using proprietary formats. It also includes support for CSS 2.1 and 3, further enhancing the browser's overall performance.
For Windows Vista users there's a new Aero "glass" style for the Mozilla browser interface. This means that developers can write Web applications that will appear to be translucent on browsers running Windows Vista with Aero turned on.
The first public beta for Firefox 3.1 should be available in late September or early October. Final release will be in late 2008 or early 2009.
Firefox 3.1 alpha 2 is available from Mozilla.