delay key fetching of OpenPGP headers until sending email
From elijah in messaging mailing list:
In the short term, we are supporting the OpenPGP header if the URL matches the sender's domain, and we delay actual key fetching until the user sends an email. It is a good idea to delay fetching for several reasons, to prevent email bugs but also because you don't want someone to be able to fill up your keyring simply by sending you a ton of email with different keys.
(from redmine: created on 2015-03-09)