Looking for explanation of some mail/news header lines.

[Rostyslaw Lewyckyj]

Let me repeat an unanswered request
---------------------------------------------------

Will somebody please point me to documentation and explanation of the
following message header lines, which get inserted by SM and are stored
at the top of each message in the message folders:
X-Account-Key:
X-UIDL:
X-Mozilla-Keys:
and if possible their contents and behaviour.

[NoOp]

Post by Rostyslaw Lewyckyj
Let me repeat an unanswered request
---------------------------------------------------
Will somebody please point me to documentation and explanation of the
following message header lines, which get inserted by SM and are stored

This identifies the mail account used. For example:
X-Account-Key: account1
means that the message was from my first mail account.
X-Account-Key: account2
means that it was from my second email account.
etc.

about:config
mail.account.account1 etc.
prefs.js
user_pref("mail.account.account1.identities", "id1");
etc.

http://kb.mozillazine.org/Filters_%28Thunderbird%29
[Account specific filters]
http://it.toolbox.com/wiki/index.php/Unique_ID_Listing
https://datatracker.ietf.org/doc/rfc1939/?include_text=1
Not sure about this one:
http://kb.mozillazine.org/Tags
<quote>
POP

A X-Mozilla-Keys: header is added to the message to store any tags, if
the message was downloaded from a POP account. For example if a message
had a Forum and a FYI tag it would be stored as:

X-Mozilla-Keys: forum fyi
</quote>

also:
http://kb.mozillazine.org/Filters_%28Thunderbird%29
[Filtering based on Tags]

Post by Rostyslaw Lewyckyj
and if possible their contents and behaviour.

[Bill Davidsen]

Post by Rostyslaw Lewyckyj
Let me repeat an unanswered request
---------------------------------------------------
Will somebody please point me to documentation and explanation of the
following message header lines, which get inserted by SM and are stored

Helps vastly. I think there are a few other things there, if you are asked if
remote images are wanted or if the message is a scam, I *think* that answer is
saved, so you don't get asked on a reread.

I did not research the hell out of that, just noted that you only get asked once
AFAIK.