> the content that's not in the original source tends to be served up as structured data via XHR- JSON usually- Yes, you can overwrite fetch and log everything

> the content that's not in the original source tends to be served up as structured data via XHR- JSON usually- Yes, you can overwrite fetch and log everything that comes in or out of the page you're looking at. I do that in Tampermonkey but one can probably inject the same kind of script in Puppeteer.