Installing SSL (LetsEncrypt or other)

Make file /etc/nginx/sites-enabled/grusher look like this

server {
    root /var/www/html;
    server_name YOUR_URL;
    charset utf-8;
    # We will be use main settings in /var/www/html/.nginx
    include /var/www/html/.nginx;

    listen 443 ssl; # managed by Certbot
    ssl_certificate /etc/letsencrypt/live/YOUR_URL/fullchain.pem; # managed by Certbot
    ssl_certificate_key /etc/letsencrypt/live/YOUR_URL/privkey.pem; # managed by Certbot
    include /etc/letsencrypt/options-ssl-nginx.conf; # managed by Certbot
    ssl_dhparam /etc/letsencrypt/ssl-dhparams.pem; # managed by Certbot
    if ($scheme != "https") {
                return 302 https://$host$request_uri;
    } # managed by Certbot
}
server {
    server_name YOUR_URL;
    charset utf-8;
    listen 8443 ssl; # managed by Certbot
    ssl_certificate /etc/letsencrypt/live/YOUR_URL/fullchain.pem; # managed by Certbot
    ssl_certificate_key /etc/letsencrypt/live/YOUR_URL/privkey.pem; # managed by Certbot
    include /etc/letsencrypt/options-ssl-nginx.conf; # managed by Certbot
    ssl_dhparam /etc/letsencrypt/ssl-dhparams.pem; # managed by Certbot
    location / {
        proxy_pass http://127.0.0.1:8080/;
        proxy_http_version 1.1;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection "Upgrade";
        proxy_set_header Host $host;
    }
}

Change on config/grusher_modules.php port in web_socket_port_for_web on 8443