Jesse Pujji in a Twitter thread on why Facebook isn’t “always listening” to you and why they don’t have to:

If me and @mrsharma get lunch, FBs systems can figure it out (still anonymously of course) How? Our devices were near each other for about an hour at neither of our houses around lunchtime. FB knows the last 10 websites each of us visited. (This is all done based on device codes not our names/personal info). It bets that we talked about a few of these websites. So after lunch, it shows us each ads based on the other person's browsing history. We didn’t discuss 9/10 of the websites the other person visited so we don’t even notice that. But the 1 we happened to discuss JUMPS out at us. And we conclude: FB has been listening!!

I am pretty regularly telling people that Facebook it’s actually listening to you all the time, but that’s not to say they’re not creepy, just that you should be creeped out by the right things. Jesse seemingly posted this thread to calm people, but it honestly sounds more creepy to me. If this thread is 100% accurate, that means that if I browse the internet for something weird, the person I hung out with could see ads for that weird thing? Cool, I feel much better…