title: localhost sent an invalid response. ERR_INVALID_HTTP_RESPONSE
body: <p>I am working on enabling http2 in nginx docker. I am getting this error when I calling to localhost. My nginx configuration file as below. </p>
  
  <pre><code>server {
  listen       2020 http2;
  server_name  localhost;
  
  #charset koi8-r;
  #access_log  /var/log/nginx/host.access.log  main;
  
  location / {
      root   /usr/share/nginx/html;
      index  index.html index.htm;
  }
  
  #error_page  404              /404.html;
  
  # redirect server error pages to the static page /50x.html
  #
  error_page   500 502 503 504  /50x.html;
  location = /50x.html {
      root   /usr/share/nginx/html;
  }
  
  # proxy the PHP scripts to Apache listening on 127.0.0.1:80
  #
  #location ~ \.php$ {
  #    proxy_pass   http://127.0.0.1;
  #}
  
  # pass the PHP scripts to FastCGI server listening on 127.0.0.1:9000
  #
  #location ~ \.php$ {
  #    root           html;
  #    fastcgi_pass   127.0.0.1:9000;
  #    fastcgi_index  index.php;
  #    fastcgi_param  SCRIPT_FILENAME  /scripts$fastcgi_script_name;
  #    include        fastcgi_params;
  #}
  
  # deny access to .htaccess files, if Apache's document root
  # concurs with nginx's one
  #
  #location ~ /\.ht {
  #    deny  all;
  #}
  }
  </code></pre>
  
  <p>Http2 listen port is 2020. I have exposed it to 2020 when the container is started.  </p>
  
  <pre><code>docker run -d --name nginx -p 80:80 -p 2020:2020 -v 
  /home/pubudu/work/nginx/nginx-tms/config/conf.d:/etc/nginx/conf.d/:ro  
  nginx:latest
  </code></pre>
  
  <p>This is the tutorial link:
  <a href="https://www.digitalocean.com/community/tutorials/how-to-set-up-nginx-with-http-2-support-on-ubuntu-16-04" rel="noreferrer">How To Set Up Nginx with HTTP/2 Support on Ubuntu 16.04</a></p>
  
  <p>Do i need to use port 443 ? is it mandatory ?
  (I didn't use ssl for this) </p>
  
  <p>If i curl this url, response like below.</p>
  
  <p><em>Warning: Binary output can mess up your terminal. Use "--output -" to tell 
  Warning: curl to output it to your terminal anyway, or consider "--output 
  Warning: " to save to a file.</em></p>
  
  <p>I know that the page is transferred as a binary in http2. I want get the nginx index page as a response. </p>
  
  <p>your help will be really appreciated.  </p>