title: Google login popup doesn't show on iframe cause the x-frame options sameorigin
body: <p>Hello to everyone my question is different from the others of the same type:</p>
  
  <p>i have an app developed on google appengine and i want to show this app on a different site of my own in an iframe.</p>
  
  <p>The app need the authentication with google credential before using the app.</p>
  
  <p>If i embed the app into an iframe and the user access to that page, and it is already logged into my app from the direct link, it works correctly. </p>
  
  <p>But if the user enter first my other website with the iframe, and it isn't logged to my app, the google login doesn't show up and he just see a white page, whilte the console show me the error:</p>
  
  <blockquote>
    <p>ERROR: Refused to display
    '<a href="https://accounts.google.com/o/oauth2/auth" rel="nofollow noreferrer">https://accounts.google.com/o/oauth2/auth</a>?.....' in a frame because
    it set 'X-Frame-Options' to 'sameorigin'.</p>
  </blockquote>
  
  <p>do you know any way to allow the google login to popup into the iframe? there is something i can do about it?</p>
  
  <p>i'm expeting the google login pop up will also show into the iframe, so the user can enter their credential and login to my app and use it correctly.</p>