Откуда берется header x-frame-options?

единственное что я писал в nginx sites-available/default:

server {
	server_name server.com www.server.com;

	listen [::]:80;
	listen 80;
	listen [::]:443 ssl;
	listen 443 ssl;

	ssl_certificate /etc/letsencrypt/live/server.com/fullchain.pem;
	ssl_certificate_key /etc/letsencrypt/live/server.com/privkey.pem;

	include /etc/letsencrypt/options-ssl-nginx.conf;
	ssl_dhparam /etc/letsencrypt/ssl-dhparams.pem;

	add_header X-Frame-Options "";

	client_max_body_size 32m;

	location / {
		try_files $uri $uri/ /index.html;
		expires $expires;
		add_header X-Frame-Options "";
	}

	location /api {
		proxy_pass http://localhost:8080;
		add_header X-Frame-Options "";
		proxy_set_header X-Frame-Options "";
		proxy_set_header Host $host;
		proxy_set_header X-Real-IP $remote_addr;
		proxy_set_header X-Real-Port $remote_port;
		proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
		proxy_http_version 1.1;
		proxy_set_header Upgrade $http_upgrade;
		proxy_set_header Connection "upgrade";
	}

	root /var/www/server.com/html;
}

Я где только не добавил
add_header X-Frame-Options "";
Но при загрузки страницы стоит sameorigin...
Как это решить?