Trustedbird 介绍
Trustedbird 是一个基于 Thunderbird 的开源邮件客户端软件。
提供的扩展功能包括：
- Enhanced Security Services for S/MIME (RFC 2634)
- Triple Wrapping: sign, encrypt, and sign again a message.
- Signed Receipts
- Security Labels
- DSN (Delivery Status Notification) ⇒ the backend is now integrated in Mozilla Thunderbird 3.
- SMTP PRIORITY extension
- Secure Headers
- SASL EXTERNAL