[sebzim4500]

I've generated a few responses to that exact prompt and did not receive ads.

Is it possible that there are instructions in OP's custom message (that you can now set in settings) that make it add links to the responses? Maybe he asks for citations and this is how GPT-4 interpreted that?

Let's be reasonable here: if the OpenAI advertising salesmen were so prolific that three different manufacturers of GPS electronics were all sponsoring them we would definitely know about it.