Comment by cxr
So is there a need for it or isn't there?
> That's different. Those are a data structure defining annotations that are meant to be stored externally.
The protocol is a separate standard.
The format is JSON-LD. Putting JSON-LD into HTML isn't a question mark. (There's info at W3C.org about how to do that, too. Not that it's necessary. You can guess what it says.)
Sorry, yes you're right the annotations can be embedded too.
But these aren't meant for direct user annotations in a general way.
The web standard doesn't define any standardized mechanism for one user to add highlights and comments, and another user to see them and edit them further.
The annotations are tools that software can use for its own purposes. They're not a user-facing feature like they are in PDF.
They're both called "annotations" but they're completely different. Completely different technologies for completely different use cases.