title: This version does not support collection view cell content view. Open this document with at least Xcode 11.0
body: <p>I was excited to check out Xcode 11 with my existing xCode project, so I started coding with the latest beta version. Today I wanted to upload my new app update but of course Apple rejected the binaries advising me, to use a GM version of Xcode 11 (not released yet) or the latest Xcode 10 app. </p>
  
  <p>I was able to revert all changes made by Xcode 11 (provisioning profile, etc.) and opened the project back in Xcode 10 but I stuck in an error saying</p>
  
  <blockquote>
    <p>This version does not support collection view cell content view. Open
    this document with at least Xcode 11.0.</p>
  </blockquote>
  
  <p>I am not able to build, archive or even open the storyboard in xCode 10. I found a single collection view in my storyboard in Xcode 11 which I created using the beta. But also after deleting the entire UICollectionViewController incl. the cells and cleaning the project, I am not able open the storyboard back in Xcode 10.</p>