[IggleSniggle]

I agree, but the confusion will continue. I read maybe a decade ago that URLs are just for network content and came away with the understanding that while URIs could include any "protocol" (like file: or smb: or about:) URLs were more specific. And thus if you wanted to talk about protocol agnostic locations, you should use URI. But that was totally wrong!!

End of the day, there is not clarity, so just use the term that will be best understood by the person you are talking to. URL is a good default, probably even for "about:"