Tryin to trawl through my saved bookmarks… it might(???) have been this link. But when I try it now, it’s an invalid URL. It was years ago. Maybe the site or domain wasn’t kept up. So I’m not completely sure that was even the right URL.

https://hfet.org/google-recaptcha-privacy-nightmare/

I searched just now and found a few sites mirroring the claim. But they did not have the technical breakdown. Here’s something from The Register.

‘You know how we can prove you’re not a robot? Because we literally know exactly who you are.’ I don’t even know if it should be called a CAPTCHA – it feels like it’s just identity verification.

That story claims too, the more you are in google’s ecosystem, the easier you can pass the recaptcha. For example, Chrome users get past easer than Firefox.

I do have working a link about the infinite captcha block technique! Blocking via an unsolvable CAPTCHA. Warning, google domain. Goes to patents.google.