What is invisible_playwright?

invisible_playwright is a drop-in replacement for the popular browser automation tool Playwright that patches Firefox so automated browsing sessions are harder for anti-bot systems to flag. The problem it addresses is that websites increasingly use fingerprinting, meaning they check hundreds of browser signals such as graphics card details, audio output, installed fonts, mouse movement patterns, and network behavior, to detect and block automated scripts. Most existing anti-detect browsers patch a Chromium-based browser at the JavaScript layer, but that approach can leave traces that advanced detection systems notice. This project takes a different approach: it patches Firefox's underlying C++ source code directly, so the values a page reads come back through the browser's normal internal paths instead of a JavaScript override. Each session automatically gets a unique, internally consistent fingerprint drawn from real Firefox telemetry data, and mouse movements follow natural curved paths rather than straight, robotic ones. Settings are controlled through preferences rather than hardcoded values, so a single setting change adjusts the spoofed value. According to the README's own testing, it scores 0.90 out of 1.0 on Google reCAPTCHA v3, compared to roughly 0.3 to 0.7 for most competing tools, and passes commercial fingerprint detection services without triggering bot, VPN, or tampering flags. The README also includes a comparison table against several commercial anti-detect browser products. You would use this for web scraping, automated testing, or any task where a browser needs to interact reliably with sites that challenge standard automation tools. The API matches standard Playwright, so switching an existing script takes about two lines of code. It is released under the MIT license and supports Windows and Linux.