I&#x27;m very happy to see work going into this topic. Hiding metadata is the major part of private communication that&#x27;s not accounted for by any major chat system. I&#x27;ve recently started studying the matrix.org specification, which seems like the best bet for a next generation chat system, but it doesn&#x27;t account for metadata privacy. It&#x27;d be very difficult to hide metadata while also offering many of the other features of a modern chat system that make it useful and convenient for people (e.g. message history that a new client can sync with later).