增加了新的状态按钮，表明接收的邮件是否使用数字签名、加密或者同时使用这两种安全机制。

A new status bar icon indicated whether email you receive was digitally signed, encrypted, or both.

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增加了新的状态按钮，表明接收的邮件是否使用数字签名、加密或者同时使用这两种安全机制。

A new status bar icon indicated whether email you receive was digitally signed, encrypted, or both.

youdao