Custom field type "selection combo": Behavior after one or more options of the “Selection combo” have been deleted

After one or more options of the "Selection combo" have been deleted, the selected values are retained in the tickets. However, they can no longer be searched for in the advanced search. It is also not apparent that there are tickets with old (deleted) values.

This could be changed so that as long as there are tickets with deleted values, these are still listed in the search with a note ("deleted").