@evan @julian @angus @nutomic similarly, a chat app might not have `inReplyTo` on every single message. in fact, the vast majority of chat messages probably won't have `inReplyTo`. in this case, building a tree would fail spectacularly. all the chat messages are grouped together by the context of being in the same room, not by being in a reply tree. the reply is just metadata, like in discord or indieweb reply-contexts or the old youtube "video replies" feature.