Mozilla has released a multi-process beta version of its Firefox browser, code named Lorentz.

“Firefox “Lorentz” provides uninterrupted browsing for Windows and Linux users when there is a crash in the Adobe Flash, Apple Quicktime or Microsoft Silverlight plugins. If a plugin crashes or freezes, it will not affect the rest of Firefox. You will be able to reload the page to restart the plugin and try again” said the browser release notes.

The multi-process, or out-of-process plugins support first started appearing in early versions of Firefox 4 back in March, but Mozilla has now almost finished the task of porting the code back to the Firefox 3.6 branch.

Out of the box, it only supports Adobe’s Flash, Apple’s Quicktime and Microsoft’s Silverlight plugins, but support for other plugins can be added via the about:config menu.

The multi-process plugin feature is only available for Windows and Linux users, with support for Mac OS X coming in the near future.

A download is available from the Firefox Lorentz website.

More news has surfaced about multi-process support for Firefox, with a prototype now completed.

Multi-process support gives each tabs, window, and plugins its own process. Browsers such as Google Chrome and Internet Explorer 8 already support this feature.

Benjamin Smedberg has blogged about the benefits of multi-processes:

• Increased stability: if a plugin or webpage tries to use all the processor, memory, or even crashes, a process can isolate that bad behavior from the rest of the browser.
• Performance: By splitting work up among multiple processes, the browser can make use of multiple processor cores available on modern desktop computers and the next generation of mobile processors. The user interface can also be more responsive because it doesn’t need to block on long-running web page activities.
• Security: If the operating system can run a process with lower privileges, the browser can isolate web pages from the rest of the computer, making it harder for attackers to infect a computer.

Firefox developer Chris Jones has posted a screencast demoing the new technology.

No word on a final release date yet, but we may see this technology in production version some time in late 2010. Currently the team are focusing on Windows and Linux versions.