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rfc 2369

Headers & MIME

List-Unsubscribe and One-Click Headers: Setup for 2026 Bulk Senders (RFC 2369 + RFC 8058)

Alaa 7 July 2026

The List-Unsubscribe header (RFC 2369) and List-Unsubscribe-Post header (RFC 8058) enable the one-click unsubscribe that Gmail and Yahoo require from senders above 5,000 messages per day since ...