Block does not pass Google Validation

There’s a problem in having the Block pass the Google Structured Data Testing Tool.
The error I get is:
“Thing is not a known valid target type for the itemReviewed property.”
I searched the web, and the issue is that “Type” should be set as a book and not Thing anymore. Also, it would require the ISBN to be added.

Also, the block generates part of the structured data in the Meta of the page, and part inline in the block itself. This creates confusion when other plugins are also injecting Meta tag (for example I get the wrong “author”).

Thank you!

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