Conveying the More Instant Messaging Interoperability Message ID in Messaging Layer Security Additional Authenticated Data

The More Instant Messaging Interoperability (MIMI) content format defines a MIMI Message ID, communicated only to members of the Messaging Layer Security (MLS) group in which the message was sent. This document defines a way to share a Message ID in the MLS Additional Authenticated Data (AAD) so it is visible to MIMI providers.