A direct message answers in the form its recipient writes in

Lemmy 0.19 (most of the threadiverse) and Mbin take a private message only
as a ChatMessage and refuse a direct Note. A direct message to one account
elsewhere that writes to us as ChatMessages now goes out as one: to it
alone, without a mention in its text, kept on the post (Post.AsChatMessage)
so the served copy and an edit match. No software name decides it.

Live against Lemmy 0.19: alice's answer to lemmyuser's private message and
another persona's message to lemmyuser arrive (29 checks). A first message
to an account that never wrote to anyone here is still a Note, which they
refuse; G-0008 keeps that open for the owner.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01LsXgEaXee4GCU1hwYgPJXw

PrivaPub/Models/Post/Post.cs

@@ -56,6 +56,7 @@ namespace PrivaPub.Models.Post
 		public bool IsFederatedCopy { get; set; }
 		public string ObjectURI { get; set; }//the Note's id
 		public string ObjectType { get; set; }//the remote object's type: Note, Article, Page, Video, Event…; null for local posts
+		public bool AsChatMessage { get; set; }//a local direct message sent as a ChatMessage: its one recipient writes to us that way
 		public string ActivityURI { get; set; }//the Create's id
 		public string ActorURI { get; set; }//attributedTo
 		public string Url { get; set; }