navigator.webdriver

How it works

The WebDriver standard, which Selenium and other automation tools are built on, says a browser must expose navigator.webdriver as true while it is being driven remotely. Chrome turns it on when it is started with its automation switch, which Selenium’s ChromeDriver and Puppeteer both pass by default. The same switch shows the “Chrome is being controlled by automated test software” bar. When a person opens a browser normally, the property is false.

It exists so that sites can treat automated traffic differently, and many anti-bot scripts check it first.

Why it matters when you run several accounts

A profile that reports true is labelled as automated before anything else is looked at. The naive fix, overwriting the property from a script, has its own tells: the replaced getter may not look native when inspected, or may sit on the wrong object. Removing the cause is cleaner than hiding the symptom.

How SoftGlaze Browser handles it

When the app launches a Chromium profile it drops Puppeteer’s page-visible default switches, the automation switch among them, and gives Chrome a fixed DevTools port, because an automatically chosen one puts Chrome into automation mode. The property is only touched if Chrome still reports true, and then with a getter that looks native, because in the app’s testing, replacing a correct value for no reason was itself enough to draw challenges. The optional fingerprint-chromium engine hides it inside the browser instead. Extra stealth patches are used only for runs without a window.