[TASK] Better distinction of fields in the backend

This patch enables a better distinction of form elements in the
backend.

Change-Id: Id5bd87eeb68aaa68ccbc284d874a22a1ff0577bb
Fixes: #50460
Releases: 6.2
Reviewed-on: https://review.typo3.org/22603
Reviewed-by: Wouter Wolters
Tested-by: Wouter Wolters
Reviewed-by: Christian Kuhn
Tested-by: Christian Kuhn