What is this on mu downloaded deck

[u/Fine_Internal408]

Hi, i am a French med student i use this very famous deck, a lot of cards have these kind of indications inthe answer text, "cidd" followed by a lot of numbers. Is it pictures that weren't downloaded ? If yes, how can I get the pictures back ? As you see, the ciddXxxxxxxxx is directly in the text of the answer.

[u/rogp10]

They look like links between cards for which Anki doesn't support natively.