At its core, it’s an extension that monitors, logs, or analyzes network activity within the browser. This includes HTTP/HTTPS requests, response headers, cookies, WebSocket traffic, and even DOM changes triggered by network events.

In an era of heightened cybersecurity awareness, the term “net surveillance” often conjures images of government agencies or corporate firewalls. But for the average Chrome user, surveillance is often self-directed—or secretly embedded—via browser extensions. These plugins range from legitimate network diagnostic tools to covert data harvesters.