[KasparEtter]

Hi layer8, thanks for the feedback! I must say that your standards for thoroughness are pretty high. Since I claimed at the very top that my article covers all aspects of modern email, I don't mind your criticism at all.

I haven't thought about the prefix chaining issue, and I'm happy to mention this in a future revision of the article. I would still argue that this is below a reasonable level of technical significance as neither conversation grouping nor message delivery is affected by it. It's more like displaying "(No subject)" instead of actually displaying no subject.

Do you have any source for what you say is an old display name convention? I've just checked the standards, and as far as I can tell after a quick glance, RFC 822 (https://datatracker.ietf.org/doc/html/rfc822#section-6) doesn't mention display names at all, and its successor RFC 2822 (https://datatracker.ietf.org/doc/html/rfc2822#section-3.4) mentions display names only with angle brackets.

PS: I have quite a few topics on my todo list, which I should add in a future revision of the article in order to live up to the claim of covering all aspects of modern email. These include MAPI, Microsoft's autodiscover mechanism, direct mailbox addressing, domain-to-domain encryption, and link rewriting in incoming mails. Some information is also no longer up to date by now.