predicate switch compares NamedNode against string literals

[Michiel-VandeVelde]

predicate is an RDF/JS NamedNode, so comparing the object directly with IRI strings never matches. As a result, neither modulus nor exponent is populated and every uncached WebID verification fails. Switch on the term's value instead.

[rubensworks]

Yep!
Probably because in the past, RDF/JS didn't exist, and these terms were strings immediately.