Just to clarify, in looking at Paddy's example profile (in both view mode and edit mode), instead of using <ref>....</ref>, Paddy is finding profiles where people simply place a url at the end of a sentence. This creates what looks similar to footnoted references, but they actually aren't.
And yes, that type of formatting is incorrect.
In my over-ten-years of being on WikiTree, I have not seen profiles doing this. I *have* seen people placing such URLs under == Sources == where yes, they generate another set of numbers within [brackets].
So, Paddy, where you see profiles like the example profile you've linked to, those "in line" links should be converted to <ref>...</ref> citations, converting the URL-only text to a full citation.