Auto-authenticating to iframe-embedded Kibana dashboard

Elastic Stack Kibana
15

Hello,
So I can use nginx to access Kibana dashboards with different users? I tried to use a variable for the user in the nginx, but my problem is when I do the GET request of Kibana Dashboard.
My nginx is like this:

location / {
  proxy_pass http://127.0.0.1:5601;
  proxy_http_version 1.1;
  proxy_set_header Upgrade $http_upgrade;
  proxy_set_header Connection 'upgrade';
  proxy_set_header Host $host;
  proxy_cache_bypass $http_upgrade;
  rewrite ^/kibana(.*)$ /$1 break;
  proxy_set_header  X-Real-IP         $remote_addr; # pass on real client's IP
  proxy_set_header  X-Forwarded-For   $proxy_add_x_forwarded_for;
  proxy_set_header  X-Forwarded-Proto $scheme;
  auth_basic "Basic Auth";
  auth_basic_user_file /etc/nginx/.htpasswd;
  proxy_set_header x-forwarded-user $remote_user;
  proxy_set_header Authorization "";
  access_log /var/log/nginx/kibana.access.log;
}

How can I access my kibana dashboards? Through a POST login request?

Thanks.