https://github.com/RupertBenWiser/Web-Environment-Integrity/...
And here's why it may be bad:
https://vivaldi.com/blog/googles-new-dangerous-web-environme...
And the HN discussion on the latter:
https://news.ycombinator.com/item?id=36875940
If you want to know more, others have written novels in these comments.