Wurdearring: 4 fan de 5 stjerren

To clarify, at least one way in which the headers are being mangled is: Message-ID keeps getting squashed to 'undefined' when it was defined prior to the change.

Dizze beoardieling giet oer in eardere ferzje fan de add-on (2.1.0).  Dizze brûker hat in eardere beoardieling fan dizze add-on.