No captcha?

Hello,
I am learning programming and just discovered this website. But I am curious, how does it protect its users from spammers (people who post illegal or annoying things) without a reCaptcha? I thought clicking this blue box is required to prove that you are not a robot, can you please share any javascript that you use for this purpose?
Thank you and have a nice day,
Brian

snifferbros?

black penis

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Keep postin' that code, georgie.

keep sniffin' that ass crack

Assfuck that penguin! Assfuck that penguin!