I would like to propose the addition of OpenPGP encryption support to the Redmine Helpdesk plugin. This functionality would enable secure communication with clients via email, ensuring that sensitive information exchanged through the plugin is protected.

Proposed Functionality:
Encryption of Outgoing Emails: Automatically encrypt all outgoing Helpdesk email responses using the recipient's public key.
Decryption of Incoming Emails: Support for decrypting encrypted replies from clients using the configured private key.

Key Management Interface:

Allow uploading and managing PGP keys for each Helpdesk user.
Store recipient public keys securely within Redmine.
Integration with Redmine User Profiles: Extend user profiles to include fields for PGP public keys to facilitate easy management.

Configuration Options:

Enable/disable PGP encryption globally or per project.
Set default encryption policies.

Benefits:

Enhanced Security: Protect sensitive client communications from unauthorized access.
Compliance: Helps organizations meet security and privacy standards like GDPR or HIPAA.
User Trust: Builds confidence with clients by demonstrating a commitment to secure communication.

Use Case:

Organizations handling confidential or sensitive customer information, such as legal, healthcare, or IT sectors, can ensure email communication security by using OpenPGP encryption through the Redmine Helpdesk plugin.

Closing:

This feature would significantly enhance the plugin's capabilities and utility for security-conscious users. If you find this idea valuable, please vote for it so it can be included in future releases!