I\'ve been testing out Selenium with Chromedriver and I noticed that some pages can detect that you\'re using Selenium even though there\'s no automation at all. Even when I
partial interface Navigator { readonly attribute boolean webdriver; };
The webdriver IDL attribute of the Navigator interface must return the value of the webdriver-active flag, which is initially false.
This property allows websites to determine that the user agent is under control by WebDriver, and can be used to help mitigate denial-of-service attacks.
Taken directly from the 2017 W3C Editor's Draft of WebDriver. This heavily implies that at the very least, future iterations of selenium's drivers will be identifiable to prevent misuse. Ultimately, it's hard to tell without the source code, what exactly causes chrome driver in specific to be detectable.