[austinpena]

I am not here to defend Meta, only clarify how data is transmitted.

Data is not salted as far as I can tell, it's normalized and hashed via SHA256. They publish SDKs for serverside integrations so you can see how the code is set up.

https://developers.facebook.com/docs/marketing-api/conversio...

[gcr]

Facebook knows the nine billion most common human names.

On my Mac, sha256() takes 288ns, so running nine billion of them to find the collision would take about 43 CPU-minutes.

[mkmk]

The whole point of sending the hash to FB is so that they can look it up against the hashes of people to whom they have served an ad.