title: Iframe Restritions
body: <p>Is there any documentation that explains what you cannot do, to make an iframe unusable?</p>
  <blockquote>
  <p>You cannot use facebook iframe because of x-frame-options is deny</p>
  <p>Twitter you cannot use iframe because an ancestor violates the following content security policy directive:&quot;frame-ancestors&quot; self</p>
  </blockquote>
  <p>Is there anywhere I can check what can and can't be set to accept an iframe</p>