RFC 8058 One-Click List-Unsubscribe

Since February 2024, Google and Yahoo enforce RFC 8058 for bulk email dispatches. Failure to comply causes messages to be routed directly to spam or rejected.

Injected Headers

Every marketing blast and automated campaign sent via MailFuz Pro automatically injects two compliant headers:

List-Unsubscribe: <https://example.com/?mailfuz_unsub=1&token=...>, <mailto:[email protected]?subject=unsubscribe>
List-Unsubscribe-Post: List-Unsubscribe=One-Click

How It Operates

1. Automated POST Handling (Gmail / Yahoo Native Buttons)

When a user clicks “Unsubscribe” in Gmail or Yahoo’s UI:

1. The mail provider issues an automated HTTP POST request to the signed URL containing List-Unsubscribe=One-Click.
2. MailFuz verifies the cryptographic token without requiring user authentication, session cookies, or CSRF nonces (per RFC 8058 specification).
3. The subscriber’s status is shifted to unsubscribed in the database.
4. MailFuz logs the opt-out telemetry event and returns HTTP 200 OK.

2. Direct Browser Click

If a human recipient clicks the unsubscribe link in a web browser:

1. MailFuz detects a GET request.
2. A branded, responsive confirmation page is presented confirming the unsubscription with a button to manage more granular topic preferences.