Developer website: Mozilla.org
As of July 2012, Thunderbird has transitioned to a new governance model, with new features being developed by the broader free software and open source community, and security fixes and improvements handled by Mozilla.
Thunderbird is a free, open-source, cross-platform e-mail and news (NNTP) client developed by the Mozilla Foundation. The project strategy is modeled after Mozilla Firefox, a project aimed at creating a Web browser.
- Calendar: Problems when editing event times, some related to AM/PM setting in non-English locales
- Unresolved - Due to changes in the Mozilla platform profiles stored on Windows network shares addressed via drive letters are now addressed via UNC
- Unresolved - Chat: Twitter not working due to API changes at Twitter.com
- OS X 10.9 or later