When a question gets closed as a possible duplicate, Community ♦ edits the post to insert the "duplicate link":
That's great! We should be directing users to the "original" question. The problem with this approach, however, is that this useful path between posts can be broken. Any user can go in and edit the post to edit or remove this link:
Or in the case of this question, a suggested edit made before the question was closed and approved afterward, can indirectly remove this link.
The result being that you have a question that was closed as a "possible duplicate", but no mention of said duplicate post at all! This is not helpful.
Therefor, I propose that the "Possible Duplicate" link box NOT be inserted into question's body. It should be separate and handled similar to the
question-status ("closed as ...") box.