GPL also gets incredibly ambiguous when it's applied to anything that isn't software written in a language like C for a personal computer. (What does "linking" even mean with respect to a Javascript library, for instance?)
People who aren't trying to get freebies from he commons without paying back never had a problem with the GPL.
So I think it would cover pretty much any JS library usage, except maybe if you just drop in a widget and don’t interact with it in any way.