I think the point is that you go to the site, and save the HTML on your local machine, and then run it from there.

It would be amazing if there was a property you could add to the <html> tag to enforce that the browser would prevent any network access or disk writes.

As it stands I think after you save the files, you would have to look into each .js file downloaded as part of the bundle to check for outgoing network requests?

The code is tiny except for vue_debug.js which is 193KB.