mailcow-dockerized/data/conf/nginx/site.conf

proxy_cache_path /tmp levels=1:2 keys_zone=sogo:10m inactive=24h  max_size=1g;
server_names_hash_bucket_size 64;

map $http_x_forwarded_proto $client_req_scheme {
     default $scheme;
     https https;
}

include /etc/nginx/conf.d/sites.active;