title: Is it possible to prefill Facebook share caption as it seems seems like some apps prefill them?
body: <p>According to Facebook Sharing policy, prefill is not allowed? 
  <a href="https://developers.facebook.com/docs/apps/review/prefill" rel="nofollow noreferrer">https://developers.facebook.com/docs/apps/review/prefill</a></p>
  
  <p>I recently tried InstaWeather and Flickr iOS apps, and they prefill the caption. So are they really allowed?</p>
  
  <p><img src="https://i.stack.imgur.com/yVWIe.png" width="320">
  <img src="https://i.stack.imgur.com/D0pgm.png" width="320"></p>
  
  <p>Can someone clarify this?</p>