If anything makes me mad, it is reCAPTCHA by Google, also known as cheap way to add rate limit and anti-abuse system. As BFU, the flow is easy - you see nothing or a checkbox which you confirm by a click. Easy.
Now try to use uBlock Origin and Ghostery and you have to select all pedenstrian lanes in the image or semaphores. Fuck this shit. And every test takes like one or two minutes. And you are annotating datasets for Google free of charge just to log in into fucking Patreon.
How reCAPTCHA works anyway? It's a service provided by Google free of charge and it seems it tracks all shit you do on the internet. Then it can say whether you are human or not, because they have your IP address (approximate location), know which browser you usually use, which version, which sites you visit (Google Analytics), stores supercookie linked to shadow profile. Probably.
reCAPTCHA doesn’t depend solely on text distortions to separate humans from machines. Rather it uses advanced risk analysis techniques, considering the user’s entire engagement with the CAPTCHA, and evaluates a broad range of cues that distinguish humans from bots.
Riiiiight. Advanced risk analysis. But how it distringuish a human before a captcha challenge is shown?