title: TYPO3 - Gridelements and nested flux content elements not visible in backend
body: <p>Extension versions:</p>
  <ul>
  <li>Flux: Fluid Integration - 9.3.2</li>
  <li>Gridelements - 8.6.3</li>
  </ul>
  <p>During an upgrade from 6.2 to 8.7.32, a website uses gridelements extension and Flux. We have some gridcontainers created with the gridelements extension and flux (CE's) nested inside these. Now the content elements are created but they don't get set properly inside the gridelement containers. Unless I create the flux elements outside the gridelement and then drag in inside.</p>
  <p>In the database I can see that the fields are not properly assigned when created inside the gridelement:
  <a href="https://i.stack.imgur.com/oAn4Y.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/oAn4Y.png" alt="enter image description here" /></a></p>
  <p><em>Don't mind the typo, &quot;Created outside parent container&quot;</em></p>
  <p>So that element with 0|0 on tx_gridelements_container and tx_gridelements_columns respectivly is not displayed in the backend and only visible in the list mode.
  <a href="https://i.stack.imgur.com/47lOj.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/47lOj.png" alt="enter image description here" /></a></p>
  <p>Now, this is strange because I checked the data types on the database and it seems alright. I had other similar pages that I've upgraded as well and no one had this issue after migrating to 8.7.32, since this issue only occurred in 6.2.x versions.</p>
  <p>The allowed elements are set to all, as well as in the other TYPO3 where this issue is not occurring. Does anyone know what could I try to fix this? I'm running out of options and I couldn't find much at TYPO3 Slack, stack overflow and similars.</p>