marking a message as "read"

[Kurt Hackenberg]

On 2019-09-06 10:50, Kevin J. McCarthy wrote:

> Both "new" and "old" are "unread".  "read" means neither new nor old.

That sounds familiar. I think that goes back about 40 years, long before 
Mutt, to how spooling of incoming messages was implemented, and the 
introduction of the non-standard header Status:.

Messages that had never seen by a mail reader were "new". Those that had 
been seen by a mail reader but not by the user were "old". Those seen by 
the user were "read".

Does Mutt store this as a single state with three possible values? 
Clearly there's some logic on top of that. Also clearly, this is 
burdened with 40 years of compatibility.