When using external JavaScript files as part of the page, some SEOs and site owners use their robots.txt file to block Google from accessing that code, unaware of the consequence.

So far, so good. However, this external JavaScript file potentially loads further JavaScript files from other CDNs. These must also be listed in the CSP: ...

It's been rumored for awhile, but it looks like Google is actually testing it now. I have been seeing hits from "Googlebot/Test" for external JavaScript files across multiple domains and from ...

Within the <script> and </script> tags it is possible to write JavaScript code or link to an external JavaScript file. Lines 2-4 show the function called mouseOver ().