That's what Russian underground hackers do to create so called "anti-detect" browsers, which can emulate different browser fingerprints. But they are commercial and closed-source.
That's useless, in fact it makes you stand out even more. There are SDKs that can differentiate based on an awful lot of signals if your user agent corresponds to your actual browser version.
Because the site can compare the user agent with navigator.platform, which your browser fills with great care.
That naturally implies we must patch the browser.
"Source code? We don't need no stinkin' source code!"
That's what Russian underground hackers do to create so called "anti-detect" browsers, which can emulate different browser fingerprints. But they are commercial and closed-source.
It probably fingerprints the browser via TLS fingerprinting.
That's useless, in fact it makes you stand out even more. There are SDKs that can differentiate based on an awful lot of signals if your user agent corresponds to your actual browser version.