Secure HTML Mail Sender for Gmail helps you send password-protected messages from Gmail. When composing an email in Gmail, the extension adds a toolbar lock button that opens a secure composer. Your message is encrypted client-side (PBKDF2 + AES-GCM) and inserted into the email as protected content. Recipients who have the extension installed can decrypt directly inside Gmail by entering the password. Recipients without the extension can still use the external decrypt page through the included button.
