title: Detect whether a page is entered through history.back
body: <p>When I return to a previous page through history.back(), that page is not newly loaded. Instead, it is displayed as it was left. This is good as it is efficient and avoids dribbling in of images.</p>
  
  <p>However, I want to run a function when the page is entered via history.back() to synchronise with the page that is calling history.back(). Is there an event firing in the called page when it is entered in this way [i.e. with history.back()]?</p>
  
  <p>Note: I have a hack using setInterval that polls for re-entry, but think it is ugly. I tried popstate but it did not fire.</p>