title: Page history - back button exists?
body: <p>Is it possible check if there is a value for history.go(-1)? I know you can't access history.previous directly.</p>
  
  <p>I am trying to stay away from document.referrer because I know it can be blocked in some instances.</p>
  
  <p>Here is what I am trying to do. I have an error page, on this page I would like to either have a BACK button (if it's not the only item in history) or a close button (if it is).</p>