in fact some of them were inherited from earlier versions.
-----------------------------------------------------------------------------------------
-accept_8bitmime boolean true main 1.60 changed to true in 4.78
+accept_8bitmime boolean true main 1.60 changed to true in 4.80
acl_not_smtp string* unset main 4.11
acl_not_smtp_mime string* unset main 4.51 with content scan
acl_smtp_auth string* unset main 4.00
once_file_size integer 0 autoreply 3.20
once_repeat time 0s autoreply 2.95
one_time boolean false redirect 4.00
-openssl_options string unset main 4.73 default to unset in 4.78
+openssl_options string unset main 4.73 default to unset in 4.80
optional boolean false iplookup 4.00
oracle_servers string unset main 4.00
owners string list unset redirect 4.00
senders address list unset routers 4.00
serialize_hosts host list unset smtp 1.60
server_advertise_condition string* unset authenticators 4.14
-server_channelbinding bool false gsasl 4.78
+server_channelbinding bool false gsasl 4.80
server_condition string* unset authenticators 3.10 (plaintext) 4.64 (others)
-server_hostname string* "$primary_hostname" cyrus_sasl,gsasl,heimdal_gssapi (cyrus-only) 4.78 (others)
-server_keytab string* unset heimdal_gssapi 4.78
+server_hostname string* "$primary_hostname" cyrus_sasl,gsasl,heimdal_gssapi (cyrus-only) 4.80 (others)
+server_keytab string* unset heimdal_gssapi 4.80
server_mail_auth_condition string* unset authenticators 3.22
-server_mech string public_name cyrus_sasl,gsasl 4.43 (cyrus-only) 4.78 (others)
-server_password string unset gsasl 4.78
+server_mech string public_name cyrus_sasl,gsasl 4.43 (cyrus-only) 4.80 (others)
+server_password string unset gsasl 4.80
server_prompts string* unset plaintext 3.10
-server_realm string unset cyrus_sasl,gsasl 4.43 (cyrus-only) 4.78 (others)
-server_scram_iter string* unset gsasl 4.78
-server_scram_salt string* unset gsasl 4.78
+server_realm string unset cyrus_sasl,gsasl 4.43 (cyrus-only) 4.80 (others)
+server_scram_iter string* unset gsasl 4.80
+server_scram_salt string* unset gsasl 4.80
server_secret string* unset cram_md5 3.10
-server_service string "smtp" cyrus_sasl,gsasl,heimdal_gssapi (cyrus-only) 4.78 (others)
+server_service string "smtp" cyrus_sasl,gsasl,heimdal_gssapi (cyrus-only) 4.80 (others)
server_set_id string* unset authenticators 3.10
shadow_condition string* unset transports
shadow_transport string unset transports
tls_remember_emstp boolean false main 4.21
tls_require_ciphers string* unset smtp 4.00 replaces tls_verify_ciphers
string* unset main 4.33
-tls_sni string* unset main 4.78
+tls_sni string* unset main 4.80
tls_tempfail_tryclear boolean true smtp 4.05
tls_try_verify_hosts host list unset main 4.00
tls_verify_certificates string* unset main 3.20