Hi,

Currently https://html.spec.whatwg.org/multipage/images.html#the-list-of-available-images says:

Each Document object must have a list of available images. Each image in this list is identified by a tuple consisting of an absolute URL, a CORS settings attribute mode, and, if the mode is not No CORS, an origin.

I think we should always attach the origin to the matching key, because that information is pretty important even for No CORS images - CORS-sameoriginness is one example.

cc: @domfarolino