I will also add that friend suggestions are a good gauge if Facebook knows who you are. After deleting every friend suggestion they offered, eventually they cycled through countries of which I have nothing to do with. I went a month with friend suggestions from Nigeria. Then it switched to Arabic countries. then South America. Countless prostitutes or LGBTQ individuals popped up as suggestions. I treated friend suggestions like a game of Space Invaders. I clicked the “x” to remove everyone that was suggested.

Be aware that even if Facebook & Twitter do not have personally identifying info on you, they will fabricate it to defraud their advertisers.

On Twitter, I regularly uncheck everything they flag me as being interested in. The first time I did that, they locked me out of my account. I replied back to customer service and cussed them out. They apologized and restored my account. Now I uncheck everything as soon as I log in. Doing so will flag them to ask for my username or phone number. No one online has my phone number nor will they ever have it.