Decision register
A specification should show its boundaries. These technologies are real, but not yet universal enough, testable enough, or in scope.
AMP for Email enables dynamic components in participating clients, but it requires a separate MIME part, sender registration, and provider-specific support. Ordinary HTML and a complete web fallback remain the interoperable baseline.
Revisit when: Multiple independent mailbox ecosystems support the same interoperable interactive-email format.
BIMI can display a brand logo in participating mailboxes when strong authentication and provider requirements are met. It does not authenticate a message and remains an optional presentation layer, so the core spec stops at DMARC enforcement.
Revisit when: BIMI reaches broad interoperable support without provider-specific certificate or policy differences.
Disposition notifications are requests, not proof that a person read or understood a message. Clients and recipients may ignore them, and automated processing can generate ambiguous signals.
Revisit when: A standardized receipt becomes reliable, privacy-respecting, and consistently controlled by recipients.