Reverse Engineering Chrome's New X-Browser-Validation Header

Chrome recently introduced several new HTTP headers, with `x-browser-validation` being particularly intriguing. This post details the reverse engineering process revealing its functionality: it concatenates a hardcoded platform-specific API key with the user's full User-Agent string, then hashes it using SHA-1 and Base64 encodes the result. This header serves as an integrity check, preventing User-Agent spoofing. The analysis dissects relevant functions within Chrome's source code and provides default API keys for various platforms.