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

To find the largest gcd >>123 after the 362 >>8 "die" posts https://dis.tinychan.net/read/prog/1582047203 are decorated:
>> Array.from (document.querySelectorAll ("div.post > div.body")).map (e => [e.innerText.match (/gcd = (\d+) = /), e.parentNode.querySelector ('button.num').innerText]).filter (p => p [0] != null).map (p => [parseInt (p [0] [1], 10), p [1].split (' ', 1) [0]]).sort ((a, b) => a [0] - b [0]).slice (-5)
0: Array [ 56, "784" ]
​1: Array [ 87, "696" ]
​2: Array [ 88, "792" ]
​3: Array [ 126, "882" ]
​4: Array [ 154, "770" ]