After fixing the broken letter through the web interface, I end up with: 00000930 64 65 6e 2e 0a 64 65 73 63 72 69 70 74 69 6f 6e |den..description| 00000940 20 3d 20 22 c3 96 66 66 65 6e 74 6c 69 63 68 65 | = "..ffentliche| 00000950 20 53 75 70 70 6f 72 74 6c 69 73 74 65 22 0a 0a | Supportliste"..| List-Id: =?utf-8?q?=C3=96ffentliche_Supportliste?= <helpdesk.csn.tu-chemnitz.de> -- You received this bug notification because you are a member of Mailman Coders, which is subscribed to GNU Mailman. https://bugs.launchpad.net/bugs/1831321 Title: the List-Id field is filled without < and > around the list-id if the description contains unsupported characters To manage notifications about this bug go to: https://bugs.launchpad.net/mailman/+bug/1831321/+subscriptions