title: Unexpected "Cannot call API on behalf of this user" after upgrading to graph api 2.10
body: <p>We've allowed sign up/access to our website using Facebook Login for a long time. Two days ago, after upgrading to graph api 2.10, this stopped working for <em>a portion</em> of our users. Myself and most others are unaffected.</p>
  
  <p>The error message received in the Access Token response reads "Cannot call API on behalf of this user". </p>
  
  <p>I can't find anything in the 2.9 -> 2.10 changelog that mentions anything remotely connected to this problem, and I've found very little on this issue externally. </p>
  
  <p>A few posts suggests that it might have something to do with insufficient privacy policy settings in our Facebook app settings, but everything is in place expect the non-mandatory Data Deletion Request URL. The fact that it also works perfectly fine for me as an EU citizen (affected by GDPR) says to me that it's something else. We do not have any country restrictions in place, and those who are affected by this comes from a variety of countries both inside and outside of the European Union.</p>
  
  <p>Does anybody recognize this problem? </p>