Internal document consistency error related to graphics

Both in Notes local names.nsf and in the mail file on the server, a user is getting the error Internal document consistency error related to graphics when saving an existing contact.

It is not a corruption. There's an unsupported image type in the rich text item designated to hold the contact picture. However, the item looks empty.

The error itself doesn't help to determine where the problem is. It should be more specific, helping the user to face out where the issue is. Not only, the rich text item should have a "not found" placeholder, or something similar, so deleting the unsupported picture would be the first thing to try. Now, there's need to focus the rich text item and hit DEL on the keyboard to remove the invisible picture.

The italian translation is even worse: Errore di coerenza interno al documento legato ai grafici
It just means something different ("grafici" means "charts").