A beta version of Mozilla's Firefox 7 is now available for Windows, Mac and Linux. Despite releasing version 6 of the popular browser earlier this week, it's the next iteration that many expect to solve persistent memory leak issues that have plagued the software for years.

Firefox 7 will introduce MemShrink, an initiative that began in June to eradicate the browser's memory inconsistencies. Mozilla developer Nicholas Nethercote claims that Firefox 7 uses less memory than the past three versions, between 20 and 50 percent less in some instances.

In addition to MemShrink, the new build also features better Javascript garbage collection. It's said to work more frequently now and should free up more memory when multiple tabs are open. The upcoming browser also implements Azure Direct2D for Canvas which increases canvas-based animations in HTML5.

There are also tools built into Firefox 7 that will help developers measure load times. Synchronization of bookmarks and passwords is said to be faster, too.

Version 7 is part of Mozilla's recent rapid deployment of browsers. The developer released Firefox 5 in June and earlier this week it quietly launched Firefox 6 a day ahead of the planned release date.

Mozilla's browser has been criticized for needing large amounts of RAM and then not freeing that memory once windows or tabs have been closed. Nethercote acknowledges these shortcomings, indicating that some versions were more efficient than others. He praised Firefox versions 3, 3.5 and 3.6 but said things deteriorated with version 4 partly because of all its new features, aggressive JavaScript garbage collection and image decoding.

The final version of Firefox 7 should be available by September 27.