Annotations don't anchor in iframe if fetched based on Dublin Core identifier #7081
Description
Minimum Example: I have two file test1.html and test2.html each contain an iframe using srcdoc or src with
<head>
<meta name='dc.identifier' content='test'>
<meta name='dc.relation.ispartof' content='strcutseeker'>
</head>
Highlight/annotation inside one iframe become orphan for another iframe.
I suspect the cause is that when receiving annotation from server, the target property of annoation is usually url rather than fingerprint-like urn:x-dc:....
Note that even if i am not using srcdoc, using src with even the same link still cause similar phenomenon; also setting test1.html and test2.html with the same dublin meta data can't fix the problem.