title: How can I persist a session in an iframe?
body: <p>Suppose I have a web app that I want to embed into any other site using an iframe.  The iframe references my site and operates independently of the hosting web page.</p>
  
  <p>Well, the browser considers the iframe to be a third party site, therefore its session cookie is considered a third party cookie.  Some methods exist to make the browsers happy (e.g. P3P header), but it's still possible the user would have third party cookies disabled entirely.  If so, then session cookies can't persist in an iframe.</p>
  
  <p>What are good methods for persisting a session in an iframe on a third party site?</p>