Message threading: reply message and In-Reply-To/References

[Kevin Shell]

On Wed, Sep 23, 2020 at 09:22:02AM +0200, Francesco Ariis wrote:
> Hello Kevin,
>
> Il 23 settembre 2020 alle 13:52 Kevin Shell ha scritto:
> > In mail/news discussion,
> > some reply messages have no In-Reply-To/References headers,
> > what cause reply messages don't have In-Reply-To/References headers?
>
> A possible explanation: the sender clicked «New message» and copy/pasted
> the Subject instead of clicking «Reply».
>
This is only one possible scenario, expecially newbies.

> > What message these reply messages
> > linked to with regard to mutt message threading?
>
> By default mutt checks In-Reply-To/References to group threads; *also*,
> messages with the same Subject are grouped together in «pseudo threads»
> (reference [1]).
> Does this answer your questions?
> —F

I know, but I ask what those messages linked to, root/first message?

--
kevin