some text/plain parts are not displayed at all (but they do appear in other MUAs when bounced from OTRS)
In this case it didn't really matter but I imagine it would sometimes cause confusion.
test case: 2014062710022031
minimized test based on that ticket that should have the same issue:
Content-Type: multipart/mixed; boundary="Boundary_(foo)"
--Boundary_(foo)
Content-type: text/plain; CHARSET=US-ASCII
Content-transfer-encoding: 7BIT
Most of the message...
--Boundary_(foo)
Content-type: image/png; name=image.png
Content-transfer-encoding: base64
Content-disposition: inline; filename=image.png
...
--Boundary_(foo)
Content-type: text/plain; CHARSET=US-ASCII
Content-transfer-encoding: 7BIT
Robert.
Robert Fulton
--Boundary_(foo)--
Version: wmf-deployment
Severity: normal
See Also:
https://bugzilla.wikimedia.org/show_bug.cgi?id=56106