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Google tries to defend its Web Environment Integrity
(techreport.com)
This is a most excellent place for technology news and articles.
All of that can be easily checked via JavaScript, but now if you world use extensions to disable those checks you would not pass the attestation.
So yeah, essentially you no longer have control over your computer, and need to bend over and accept everything the site owner wishes to do.
Including a malicious site owner's wishes.