title: Strange array.push in JS
body: <p>I have simple code </p>
  
  <pre><code>sites_from_session = 12;
  function function_name () {
      var items_to_send = sites_from_session;
      var template_name = jQuery('#new-site-template-name').val();
      console.log(sites_from_session);
      items_to_send.push(template_name);
      console.log(sites_from_session);
  }
  
  
  function_name();
  function_name();
  function_name();
  function_name();
  function_name();
  function_name();//...
  </code></pre>
  
  <p>The problem is that the <code>push</code> method pushes value to both arrays</p>
  
  <p><img src="https://i.stack.imgur.com/stW7o.png" alt="enter image description here"></p>
  
  <p>Where i am wrong?</p>