Due to the glib update in debian I was forced to compile mission-control myself from
https://github.com/TelepathyIM/telepathy-mission-control.
Unfortunately the mcp-account-manager plugin of telepathy-ofono doesn't compile against it.
I'll try to figure out what's wrong myself later, but maybe someone here who is more experienced with Telepathy already knows.
See https://paste.cutelyst.org/9OJWhX_oQ for the compilation log.