The form to set a display page is visible but after publishing it is not set.
Environment
DXP 7.2
Resolution
Only display page templates should be selected for documents. Web Content should be the only one that allows widget pages with default Asset Publisher as display page. The option of selecting Public pages as display pages for documents was removed by LPS-105562. You can also see the explanation in this comment.
A hotfix can be requested from Liferay Support that will remove the option from documents.
