Although intended for developers and testers only, the browser is stable enough for an everyday use and includes several new features like the ability to drag and drop tabs between browser windows and support for HTML 5 tag elements.
Most of the other features though are purely aesthetics, which could point to the fact that the bulk of the improvements under the hood, have already been done and that tweaks as from now will only be minor.
That said, there's an initial implementation of Web Workers which should allow for a more responsive Javascript engine.
Mozilla's new Javascript Engine which is said to be at least as good as the one in Google Chrome is not included in this development milestone but can be seen in action instead in the browser's nightly build.
Firefox's browser should be ready for a Beta launch by the end of this month and will get a candidate release by next month.

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