Subject: bug#43462: 28.0.50; Add Protected-Headers support

From: Morgan Smith <[email-masked]>
Date: Wed, 16 Sep 2020 21:41:20 -0400

My co-workers use enigmail to encrypt subject lines.

Implementing this draft for protected headers would allow Gnus to
encrypt and decrypt subject lines.

https://datatracker.ietf.org/doc/draft-ietf-lamps-header-protection/