Update..

roles/common/templates/usr/local/src/mailsystem/conf/install_update_dovecot.conf.j2

@@ -52,6 +52,14 @@ ipv4="{{ ipv4_address | default(omit) }}"
 ipv6="{{ ipv6_address | default(omit) }}"
 
 
+# - Webserver User
+# -
+# - defaults to:
+# -    http_user=www-data
+# -
+#http_user="www-data"
+
+
 # ---
 # - Listener configuration
 # ---