The development process of Mozilla’s email client moves on with the release of the 3rd Beta installment of the upcoming Thunderbird version 3. The latest stable version of the Mozilla developed email client is Thunderbird 2.0 – version 2.0.0.22 is a security update that is meant to make the software safer and protect the user from attacks and other security incidents.

“We're happy to announce the release of Thunderbird 3 Beta 3, now available for download. Thunderbird 3 Beta 3 is available for testers, extension developers, and other people who are curious to follow the development of the next release of Thunderbird. This milestone is focused on testing the core functionality of the new features and platform changes that will be included in Thunderbird 3” said Mozilla’s press release.

Thunderbird 3 Beta 3 will not be the last Beta version in the development cycle of the email client. According to the Mozilla Foundation, as the organization works on what it calls a “major new release of Thunderbird 3”, you can expect a 4th Beta to be rolled out in the future.

Mozilla would appreciate it if Beta testers would put this release through its paces and provide feedback on the following changes and new features:
- Improvements For Developers: thread pane and tab refactoring, extension fixes.
- User Experience Improvements: tabbed email messages, message summary view, column headings, smart folders, enhanced integration with Gmail.

If you would like to get Thunderbird 3 Beta 3, a download location is available here.

In related news, Mozilla rolled out updates for other products as well:
- Firefox 3.5.1 which addresses a critical security vulnerability in the Just-in-Time Javascript compiler (details here).
- Firefox 3.0.12 which plugs a total of 6 security holes, 5 of which having been deemed by Mozilla’s security team as “critical” (details here).