title: Unrecognized content security policy directives: disown-opener, reflected-xss, referrer
body: <p>I'm at least 90% sure that the following is a result of Chrome's implementation of <a href="https://www.w3.org/TR/CSP/" rel="noreferrer">W3C's CSP standard</a>, but I thought that it'd be best to double down and make sure.</p>
  
  <p>I'm currently in the process of implementing a strict content security policy for a client, and I've run into the following policy directive complications on Chrome 66:</p>
  
  <pre><code>Unrecognized Content-Security-Policy directive 'disown-opener'.
  Unrecognized Content-Security-Policy directive 'reflected-xss'.
  Unrecognized Content-Security-Policy directive 'referrer'.
  </code></pre>
  
  <p>Again, I'm sure this is a standards issue (as I'm using <a href="https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Security-Policy" rel="noreferrer">MDN’s CSP documentation</a>). If this is the case, can anyone direct me to competing or substituting directives?</p>