Dovecot: Fatal: Error in configuration file /etc/dovecot/dovecot.conf: protocols: Unknown protocol: sieve

1.0 Error:

While configuring the Dovecot Mail Delivery Agent, the Dovecot server would not start and the following error messages were printed.

$ sudo systemctl start dovecot
Job for dovecot.service failed because the control process exited with error code. See "systemctl status dovecot.service"
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