Mozilla, the non-profit organization behind the Firefox web browser and other pieces of software, today released Firefox 17, the newest release of the popular web browser. This newest iteration comes just one month after the release of Firefox 16.

Additions are fairly light for 17, with Mozilla adding only a Social API and support for Facebook Messenger integration, as well as a new click-to-play feature that prevents certain plugins from starting without express permission from the user. There are around 20 performance improvements, as well, to keep Firefox running faster than the competition.

Most importantly, however, may be Firefox 17′s subtractions: there is no longer support for OS X 10.5 Leopard. Leopard was released way back in 2006 after the Intel transition, and was the last version of Apple’s OS X operating system to support legacy PowerPC Macs. According to Mozilla, this “will free up resources for new Mac features like Native Full Screen support and new Mac accessibility tools,” which the Mac version of Firefox has been missing for quite some time.

Of course, this release isn’t just about Macs: Windows and Linux machines also share in the improved performance and social aspects of Firefox 17, which, by the way, is available to download at the source link below – unless, of course, you are running Leopard.

[Firefox: 1, 2 via Engadget | Download Firefox 17]