2. Evasion, Debugger, & Anti-Stealth Traps
toString Interrogation
Detection approach
Function.prototype.toString integrity violation detected. puppeteer-extra-plugin-stealth patches toString with a Proxy in _utils/index.js to hide its evasions. Real browsers have unmodified native toString functions.
How this helps detect bots
This signal is assessed with other independent session, browser, and network evidence. A single anomaly is a lead, not a verdict; corroborating anomalies make automated traffic more likely.
Legitimate traffic to consider
Secure custom enterprise builds or local proxy tools overriding the toString method.