I wrote about this a year ago on my blog: https://planiverse.wordpress.com/2019/01/11/advertising-to-⅔...

In short, the fake accounts had several factors in common: - No or almost no public posts. - The only public posts being an update of the cover photo and profile photo in 2017. - The profile photos tended not to be headshots: a photo of a cup of coffee, say, or a landscape. - Between 20-100 friends. - Friends tended to be in places like India, the Middle East, or Southeast Asia. - Their gender didn’t match the name or photo about half the time: a “Martha” referred to as “he” by Facebook, for example.