Due to the GDPR Facebook added all kinds of new controls. I looked through them today.

Stuff Facebook has tracked, despite not using their app on my phone (preloaded but completely disabled) and using their website only with uBlock Origin):

a) everywhere you ever used Facebook to login to a website. I thought I never did this but apparently I still had 5+ websites linked to this. They seem to use this to profile you. Facebook mentions about this _"These are active apps and websites. This means that you recently logged in to them using Facebook, and they can request information you've chosen to share with them."_ I never wanted to share anything, but Facebook often changes settings or pretends I did

b) every time you connected an app to your Facebook account. Apparently I again did at a few times (to easily upload some photos). I also saw old phones in here, Runkeeper (don't recall using that), Tinder (haven't used in years). All of those seem to forever be able to get information from you.

c) topics (yet another new name). Not sure how they figured things like that out. Fortunately you can completely disable the personal tracking, though you need to do that in various different places.

d) advertisers whom added their contact list to Facebook. Really!! So some other company shared my details with Facebook. Which means they've also shared details of people not using Facebook with Facebook.

e) used websites and apps. This is surprisingly accurate and complete (hundreds of sites+apps!), despite having the Fb app disabled plus always using uBlock Origin. I really wonder if they somehow are able to retrieve the browser history. It seems Facebook also tracks you using "apps using Facebook technology", which I guess is a library to show ads or something which uses the app permissions to further track the user.

f) it uses your profile (relationship status, employer, job title, education) to targets ads

g) somehow puts you into categories. E.g. "uses a mobile device (xx to xx months)". I disabled this crap yesterday, it updated it today with more information. I assume through Whatsapp/Instagram or maybe some kind of Facebook ad library? Again, I don't want it to track me, yet they seem to be easily able to do this. I turned off all the settings but apparently still missed a few.

i) ads topics. Not sure how topics differs from the 3 other ways they call this.

j) your location. It doesn't show what it does with this. You cannot disable the location tracking; it suggests to turn it off in the phone settings (which is a cop-out). I'll need to download my data to further determine this. I'm pretty sure Facebook is big enough to figure out additional ways of location tracking than just what Android/iPhone allows.

k) websites visited. I assume any link clicked. This is somehow different than all the other ways it already showed websites.

l) the existing "Who can contact you using email address / phone number". It says "Who", but it is used for the API as well, that's not a user so I find the usage of "Who" misleading.

Despite doing all of this, still not sure how to prevent something like Cambridge Analytica from downloading my data through others ("friend"). Further as I already mentioned it seems to continue tracking me despite turning everything off. Not cool.