Navigator: webdriver property

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since ⁨May 2018⁩.

Thewebdriver read-only propertyof thenavigator interface indicates whether the user agent iscontrolled by automation.

It defines a standard way for co-operating user agents to inform the document that itis controlled byWebDriver, for example, so thatalternate code paths can be triggered during automation.

Thenavigator.webdriver property is true when in:

Chrome: The--enable-automation or--headless flag is used, or the--remote-debugging-port flag specifying port 0 is used.
Firefox: Themarionette.enabled preference or--marionette flag ispassed.