Instead of commenting on the author, perhaps we could share an example of the appropriate nginx config:

  upstream http_backend {
      server 127.0.0.1:8080;
  
      keepalive 16;
  }
  
  server {
      ...
  
      location /http/ {
          proxy_pass http://http_backend;
          proxy_http_version 1.1;
          proxy_set_header Connection "";
          ...
      }
  }

https://nginx.org/en/docs/http/ngx_http_upstream_module.html...