I just enabled memcached from studio settings, www.example.com/studio/settings.php and it works perfectly on all previous versions, except this version.

my default.conf :

server {
    listen 8080 default_server;
    server_name localhost;

    root /opt/una;
    client_max_body_size 2048M;

    ###########################################################################
    ## Client Timeout                                                        ##
    ###########################################################################

    ## request timed out -- default 60
    # read timeout for the request body from client, its set for testing purpose
    client_body_timeout 3600;

    # how long to wait for the client to send a request header, its set for testing purpose
    client_header_timeout 3600;

    # server will close connection after this time
    keepalive_timeout 3600;

    ## if client stop responding, free up memory -- default 60
    send_timeout 3600;

    ## Reset lingering timed out connections. Deflect DDoS.
    ## allow the server to close connection on non responding client, this will free up memory
    reset_timedout_connection on;

    ###########################################################################
    ## Proxy Timeout                                                         ##
    ###########################################################################

    proxy_connect_timeout 3600;
    proxy_send_timeout 3600;
    proxy_read_timeout 3600;

    ###########################################################################
    ## Location /                                                            ##
    ###########################################################################

    location / {
        index index.html index.htm index.php;

        rewrite "^/page/(.*)$" /page.php?i=$1 last;
        rewrite "^/m/(.*)$" /modules/index.php?r=$1 last;
        rewrite "^/s/([a-zA-Z0-9_]+)/([a-zA-Z0-9\.]+)" /storage.php?o=$1&f=$2 last;

        if (!-e $request_filename) {
            rewrite  ^/(.+)$  /r.php?_q=$1  last;
            break;
        }

        # Block requests with suspicious patterns
        #if ($query_string ~* "(\%60|\%7C|\%26|\%24|\%3B|\%28|\%29)") {
        #return 403;
        #}
    }


    index index.php index.html index.htm;

    location ~ \.php$ {
        fastcgi_pass php:9000;
        fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
        include fastcgi_params;

        # Timeout
        fastcgi_connect_timeout 3500;
        fastcgi_send_timeout 3500;
        fastcgi_read_timeout 3500;

        # Buffers
        fastcgi_buffer_size 128k;
        fastcgi_buffers 8 256k;
        fastcgi_busy_buffers_size 512k;
        fastcgi_temp_file_write_size 512k;
    }

    ###########################################################################
    ## serve static files directly Tanks to Alex T https://una.io/u/alex-t   ##
    ###########################################################################
   
    location ~* ^(/cache_public/|/plugins_public/|/modules/|/studio/|/template/).+\.(jpg|jpeg|gif|css|png|js|ico|svg|eot|ttf|woff|woff2|)$ {
        access_log        off;
        expires           1h;
        # root /opt/una
        # add_header Cache-Control "public";
        try_files       $uri =404;
    }

    ###########################################################################
    ## deny access to hidden files                                           ##
    ###########################################################################

        location ~ /(\.ht|\.git) {
        deny  all;
    }

    ###########################################################################
    ## deny access to specific folders                                       ##
    ###########################################################################

    location ~ ^/(cache/|storage/|logs/|plugins/|tmp/) {
        deny  all;
    }

    ###########################################################################
    ## Memcached Integration                                                 ##
    ###########################################################################

    location /memcached {
        # Example using just the URI as the key
        # set $memcached_key $uri;
        # Set the Memcached key with the prefix
        # set $memcached_key "${key_prefix}${uri}${is_args}${args}";

        # Example with query parameters included
        #set $memcached_key $uri$is_args$args;

        # Example with a custom key
	    # set $memcached_key "key-$uri-$arg_user_id";
        set $key_prefix "site1_";
        set $memcached_key "${key_prefix}${uri}${is_args}${args}";

        # Pass the key to the Memcached server
        memcached_pass dragonflydb_cluster;

        # Define the response type
        default_type application/json;

        # Handle errors
        error_page 404 = /memcached_not_found;
    }

    location = /memcached_not_found {
        return 404 "{\"error\": \"Not found in Memcached\"}";
    }
}

my mecached.conf

upstream dragonflydb_cluster {
    server 127.0.0.1:11211;
    server 127.0.0.1:11212;
    server 127.0.0.1:11213;
}

And indeed I have a cache for requests in front of the site, It's still experimental but it speeds up my website

my reverse proxy: https://github.com/kabballa/una-reverse-proxy