Besides Firefox 24
being shipped, Mozilla is also ready to ship Thunderbird 24, a major update at long last to their open-source e-mail client.
Mozilla Thunderbird doesn't see quite the development love or adoption that Firefox has experienced, but it's still around and loved by many (including by your's truly). Thunderbird 24 has performance improvements, a horde of bug-fixes, the Twitter API has been updated to version 1.1, emails can now be sent to IDN based email addresses, corrections to LDAP passwords, improvements to the chat functionality, and a lot of other minor improvements throughout the multi-platform email program.
While the official release announcement for Thunderbird 24 has yet to be issued, the builds (and source) for 24.0 are available from this FTP directory