You can see EFF PrivacyBadger code getting injected in the source tab in dev tools, not positive about network requests. It wouldn't be hard to test though, jus

You can see EFF PrivacyBadger code getting injected in the source tab in dev tools, not positive about network requests. It wouldn't be hard to test though, just make a simple extension that does XHR to example.com and load it up locally. Chrome extensions are surprisingly easy to write, and there are some simple tutorials if you google around a bit :) EDIT: here's how to inspect extensions you're curious about: https://developer.chrome.com/extensions/tut_debugging https://developer.chrome.com/extensions/tut_debugging