Package: neomutt
Version: 20220429+dfsg1-4.1
If my .muttrc configuration includes the line:
set smtp_authenticators="gssapi"
then Neomutt gives an error on startup while processing the
configuration file, citing the above line: "Option smtp_authenticators:
gssapi is not a valid authenticator".
It correctly authenticates to the server via IMAP with Kerberos/gssapi.
Furthermore, Mutt (i.e., from the Mutt package) correctly processes the
above configuration.
If I recall correctly (and I don't have a system available for checking
at the moment), the Neomutt package under Arch Linux, which is probably
closer to upstream, does not have this bug; it may be Debian-specific.
