Mozilla, the non-profit foundation responsible for the popular Firefox browser has announced the release of version 13 of their Thunderbird email client, bringing a number of changes including hundreds of bug fixes and the addition of a new custom email address creation feature.

The latest version as part of Mozilla's rapid release cycle includes improved support for sending of large email attachments, as well as a new partnership with YouSendIt, a commerical file sharing service which Thunderbird users can register to and then use to privately send files larger than the email client's maximum attachment size. Over 200 bugs have also been fixed, including many that caused the email client to crash and Mozilla says the overall start-up time as well as stability have been improved.

Perhaps the biggest change is a new feature that will allow Thunderbird users to register a new domain during the process of setting up a new email address. Personalized email domains are backed by companies Hover and Gandi, who both handle domain registration and email hosting. Thunderbird will also setup the new personalized email address so its immediately ready to send and receive messages.

"If you've ever dreamt of having a personalized email address (such as "" or "") for you, your family or your business, Thunderbird has made it simple! In partnership with Gandi and Hover, we've made it possible to sign up for a new email address directly from within Thunderbird," said Anne-Marie Bourcier on Thunderbird's official blog.

Mozilla also pointed out to those still using versions 3.x.x of the email client that it's no longer supported and poses a security risk. Also, the system requirements have changed for those using Windows, with users now requiring Windows XP Service Pack Pack 2 or later.

Thunderbird 13 is available for immediate download on Linux, OS X and Windows.

Image credit: Ars Technica