I built this list with the Activity window from an old release of Safari. I expect there's lots of ways you could do it, I often contemplate such ways but this way works pretty well.

Just open the Activity window then visit a few random, at least somewhat sketchy websites. Pop-culture news sites are good. You'll see lots of 43 or 60 byte GIFs, commonly they will have lots of query parameters in the URLs, sometimes I see one-byte javascripts.