How can we improve WHMCS?

Current Situation:
- WHMCS can successfully import emails from the authenticated user mailbox.
- Emails from a shared mailbox are not imported.
- Full Access has been granted in Exchange, and OAuth app is configured with delegated permissions including Mail.Read.Shared.

Technical Explanation:
Currently, WHMCS uses the Microsoft Graph API endpoint:
GET https://graph.microsoft.com/v1.0/me/messages

This only retrieves messages from the authenticated user’s mailbox, even if Full Access to a shared mailbox is granted.

The correct endpoint for accessing a shared mailbox is:
GET https://graph.microsoft.com/v1.0/users/{shared-mailbox}/mailFolders/inbox/messages

with the same delegated access token.

Challenges:
1. Delegated permissions alone (Mail.Read.Shared) do not allow WHMCS to access shared mailbox messages via the /me/messages endpoint.
2. Manual Full Access in Exchange allows web access, but Graph API requires mailbox-specific shared permissions.
3. Current WHMCS email import functionality does not support querying shared mailboxes directly.

Request:
Please add native support for importing emails from shared mailboxes in WHMCS via Microsoft Graph API. Specifically:
1. Confirm which delegated permissions are sufficient for WHMCS to access shared mailboxes.
2. Implement support for using the /users/{shared-mailbox}/mailFolders/inbox/messages endpoint for shared mailbox imports.
3. Provide guidance or automated configuration for any additional Exchange settings (e.g., automapping, propagation delays).

Expected Outcome:
- WHMCS can fetch emails from shared mailboxes using OAuth delegated access, without requiring a separate license for the shared mailbox.
- Simplified setup for departments using centralized support mailboxes.
- Consistent behavior with Microsoft Graph API best practices.

Impact:
- Reduces manual workarounds for shared mailbox access.
- Improves integration reliability with Microsoft 365.
- Enhances WHMCS usability for organizations using shared support mailboxes.