title: Close icon and window.open : feasibility and handling
body: <p>I am putting up a new window like so:</p>
  
  <pre><code>var myWindow = window.open('', "RWindow", "dialog=yes, close=no, height=900, width=1400, top=70");
  </code></pre>
  
  <p>I have modified the relevant configuration parameters of the user agent (Firefox 58.0.1) —refer to: <a href="https://stackoverflow.com/questions/1023644/firefox-and-universalbrowserwrite-privilege">Firefox and UniversalBrowserWrite privilege</a></p>
  
  <p>Mozilla window.open API ( 
  <a href="https://developer.mozilla.org/en-US/docs/Web/API/Window/open#Window_features" rel="nofollow noreferrer">https://developer.mozilla.org/en-US/docs/Web/API/Window/open#Window_features</a> )
  specifies a <strong>close</strong> feature (that requires a privilege):</p>
  
  <pre><code>When set to no or 0, this feature removes the system close command icon and system close menu item. It will only work for dialog windows (dialog feature set). close=no will override minimizable=yes.
  </code></pre>
  
  <p>to no avail for me (please see the code quoted hereabove). What is it I am doing wrong?</p>