This is a simple, elegant HTML+CSS copier. I looked through the code, and it makes no external calls, so it is completely safe to use.

However, it does not work if you have ANY extensions which load CSS into the page's DOM. If you have an ad blocker, ghostery, whatever, this extension will always fail with the error "CSSStyleSheet.rules getter: Not allowed to access cross-origin stylesheet".

There is a solution to this problem on the page betterprogramming dot pub/how-to-fix-the-failed-to-read-the-cssrules-property-from-cssstylesheet-error-431d84e4a139 so I hope the author can fix this problem because it would be a really useful extension.