Web software company Mozilla has released a beta version of its Firefox browser, improving memory and speed along with new audio features.

Firefox 15 looks set to prevent most memory leaks caused by add-ons, significantly reducing memory consumption without requiring upgrades for add-ons.

The web browser say add-on memory leaks will be cleaned out in the new system given their modal is faster meaning less likely to crash after criticisms over past memory practices.

Firefox 15 also supports the free audio format Opus via Opus reference implementation after recently being approved for publication.

Features include better compression formats for MP3, improved music and speech functions supporting both interactive and pre-recorded applications.

Firefox 15 is scheduled for availability August 28.