#3090: Mutt removes In-Reply-To header field Comment (by pdmef):
In another case reported by exg on #mutt the problem is not >1 @ signs but something other than exactly 1 including 0. IIRC In-Reply-To isn't supposed to contain only exactly some message-id but may also contain things like "message <message-id> sent by <user> on ...". That's why mutt needs a heuristic of exactly one @ symbol to locate the message-id. However, I don't know if clients really/still generate something like that and how common it is in mail archives. But I think I prefer a solution not touching that heuristic. A fix could be to avoid writing out In-Reply-To and use References instead which still gives the user the chance to manually adjust threads in the editor. So this could be the same issue as #1935. -- Ticket URL: <http://dev.mutt.org/trac/ticket/3090#comment:4>
