Thunderbird
Thunderbird 是 Mozilla 开发的免费开源电子邮件客户端，支持多种邮件协议，具有强大的邮件管理功能。
主要功能：
- 支持IMAP、POP和SMTP协议
- 强大的邮件过滤和标签功能
- 支持加密邮件
- 可扩展的插件和主题系统
Thunderbird is a free, open-source email client developed by Mozilla, supporting various email protocols with powerful email management features.
Main Features:
- Supports IMAP, POP, and SMTP protocols
- Strong email filtering and tagging options
- Supports encrypted emails
- Extensible with plugins and themes