Facebook group recommendations are scary

So, first time I got a bit freaked was when I was searching one thing on the internet and same day there was a group based on that recommended to me on facebook. Then I was listening to one band’s album using my music player on phone and I went on facebook the same day and there it was, a group recommendation for that band’s fan group. I deinstalled both facebook and messenger from my phone.

Today I was listening to one specific artist on youtube on my phone and when I went on facebook later on my pc, group recommendation was for that artist’s fan group.

How the hell does Facebook do that? It’s like my youtube channel(google account) and facebook are connected.

Found here