Now 4chan asks for email verification
(boards.4chan.org)
4chan has been a honeypot for a long time now. Anything that uses captcha verification is sending your info to a third party (probably feds) and even if you're using a proxy or whatever else, the captcha is still fingerprinting you with your browser specs, etc. I'm sure they have it set up to determine if you're right-handed or left-handed based on where you click on the captcha images or take your actual fingerprints from your in-screen fingerprint reader.