I was surprised that @primal and @Damus don't support markdown in DMs. I don't think NIP-04 specifies what type of content should be allowed/supported. Any particular reason that markdown isn't supported @jb55 in Damus for example? Technical reasons or a good PR? Re: 
GitHub
Nostr notifications are not well formatted in Primal and Damus clients · Issue #3436 · lnbits/lnbits
Problem Nostr notifications sent by LNbits are not well formatted when viewed in popular Nostr clients like Primal and Damus. The formatting could ...