Right now we treat import() as a "new" module script graph, i.e. it calls fetch a module script graph directly. This then uses "client" as the referrer, i.e. it uses the base URL of the appropriate settings object.

But this seems semantically wrong. import() knows what script it's being called from; it uses that information to compute URLs and and fetch options. It should also use that to compute the referrer information.

Found by @jonco3. /cc @whatwg/modules. I will try to work on a spec fix and tests for this soon...