CORS - Nginx

server {
    server_name _;
    listen 80;
    access_log /var/log/nginx/access.log vhost;
    # add_header Strict-Transport-Security "max-age=31536000" always;

    proxy_hide_header Access-Control-Allow-Origin;
    proxy_hide_header X-Frame-Options;
    proxy_hide_header Content-Security-Policy;
    #
    add_header X-Frame-Options "ALLOWALL";
    add_header Content-Security-Policy "frame-ancestors 'self' '<Domínio>'";
    server_tokens off;
    proxy_cache_bypass $http_upgrade;
    client_body_buffer_size 10M;
    location / {
        add_header Cache-Control no-cache;
        expires 0;
        if ($request_method = 'OPTIONS') {
            add_header Access-Control-Allow-Origin $http_origin always;
            add_header Access-Control-Allow-Credentials 'true' always;
            add_header 'Access-Control-Allow-Methods' 'GET, POST, OPTIONS';
            #
            # Custom headers and headers various browsers *should* be OK with but aren't
            #
            add_header 'Access-Control-Allow-Headers' 'DNT,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type,Range,Authorization,accept-language';
            #
            # Tell client that this pre-flight info is valid for 20 days
            #
            add_header 'Access-Control-Max-Age' 1728000;
            add_header 'Content-Type' 'text/plain; charset=utf-8';
            add_header 'Content-Length' 0;
            return 204;
        }
        add_header Access-Control-Allow-Origin $http_origin always;
        add_header Access-Control-Allow-Credentials 'true' always;
        proxy_pass http://127.0.0.1:8080;
        proxy_redirect off;
    }
}