On 2020-09-23 03:22, Francesco Ariis wrote:
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».
Another possibility is that the sender's mail reader just doesn't do
that. Those two headers are optional, not required; some mail readers
just don't create them in replies.
