Maybe an odd question but Pornhubs start page are actually recommendations based on your viewed videos.

I suppose most folks here use incognito mode so, no cookies, clean state on each launch. Yet, if you launch another incognito window for the site, you will realize it remembered your viewing behavior and the videos reflect it.

But how do they do this? There is no account, no cookies, no local storage. And technically, they wouldn't be allowed to track you in the first place due to the GDPR.

Yet, it's the case. Anyone know how they achieve this?

EDIT: why do so many new comments just post "pornhub" or some actors name here? This isn't a search form my precious little bots