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

Here's a filter for those posts whose posters have conceded that they do not have any images available from news organizations that would expose themselves to lib3l suits, so they have to resort to their own shops. It'll be upgraded as needed, such as by improving the regex.

Array.from (document.querySelectorAll ("div.post > div.body")).filter (e => /[.]imgur[.]/.test (e.innerText)).forEach (e => { e.innerHTML = "Here's my shop on imgur."; })