Also, make sure to disable any third-party extensions while testing the CSP implementation so that they don’t interfere with the violation reports rendered in the console. You should also use a recent browser version, preferably Chrome, as it has the best support for CSP level 3 directives at the time of writing this article (November 2020).
Follow the steps in the relevant How To Install Node.js tutorial for your operating system to set up a Node.js development environment.
The code could be from the same origin as the root document, or a different origin. When the browser loads a page, it executes a lot of code to render the content.
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