Mozilla forges ahead with Firefox 3.6

Mozilla debuts Firefox 3.6, introducing significant under-the-hood changes that make it faster, help it render content better, and a few visual tweaks, as well.

Mozilla debuted Firefox 3.6 on Thursday, introducing significant under-the-hood changes that make it faster, help it render content better, and a few visual tweaks, as well. Available for Windows, Mac, and Linux, the most apparent changes in Firefox 3.6 are improvements made to the TraceMonkey JavaScript rendering engine, making it about 20 percent faster than when it debuted in Firefox 3.5, according to Mozilla. Although this makes it more competitive with Google Chrome, but not faster, there's more to Firefox 3.6 than speed.

Firefox 3.6 beta 1 will show individual preview windows for each tab on the Windows 7 taskbar. (Credit: Screenshot by Seth Rosenblatt/CNET)

Firefox maintains its reputation as the most customizable browser around, introducing default support for the next generation of Themes, called Personas. Users will no longer have to download the Personas add-on to get its on-the-fly skinning power. However, Windows 7 interface support, including tab previews using the Ctrl+Tab hot key, jump lists, and multiple tab previews in Aero Peek will have to wait for another revision. Currently, these can only be activated by changing settings in about:config.

Several notable improvements keep Firefox abreast of current browsing tech. Significant under-the-hood changes include blocking third-party software from encroaching on Firefox's file system turf to increase stability; support for the Web Open Font Format, which means users viewing pages in other languages should see faster load times via downloadable fonts; and support for the File interface, which can help with tasks such as uploading multiple photos and is part of the draft HTML5-standard effort. Open, native video can be displayed full screen and supports poster frames, which is the preview image you see before a video begins, and the new CSS attributes gradients, background sizing, and pointer events will work in Firefox 3.6.

HTML5 support debuted in Firefox 3.5, and Firefox remains the leading Web browser that supports it. This is not insignificant, because even with Google Chrome grabbing more than 4 percent of the browser market in its first 16 months, Firefox maintains a commanding 24 percent that hasn't stopped growing, second only to Internet Explorer.

A deeper change to the browser is that it is now running scripts asynchronously, which can help to load a Web page faster by putting off some work until the high-priority chores are complete. Firefox 3.6 also isolates out-of-date plug-ins so they do not become a security risk.

Unlike Firefox 3.5, which was more about keeping the browser current rather than blazing new trails, Firefox 3.6 is once again taking some small but innovative steps. Expect more new features to debut in minor-point updates as the browser works towards Firefox 3.7.