use of UIDs vs. MSGID

[martin f krafft <madduck@xxxxxxxxxxx>]

OfflineIMAP uses the X-OfflineIMAP-x... header to identify messages,
and the IMAP server's UID notion to link them to the server copy.
Since we're dealing with mail all along, and mail messages have
a unique message-id header, I wonder why that's not being used. It's
likely to be indexed on the server and could thus increase the speed
of searches.
Also, why does OfflineIMAP store headers like

  X-OfflineIMAP-x825313192-7365616d75732e6d61646475636b2e6e6574-494e424f58:
  1186324387-0249694837446-v5.99.0

?

As in, why is the header label not constant? And what do all these
numbers mean?

Cheers,

-- 
martin;              (greetings from the heart of the sun.)
  \____ echo mailto: !#^."<*>"|tr "<*> mailto:"; net@madduck
 
"man kann die menschen nur von ihren eigenen meinungen überzeugen."
                                                    -- charles tschopp
 
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