The General Data Protection Regulation (GDPR) in Europe and the CCPA in California mandate strict user consent for data tracking. If Facebook had a URL that revealed exactly which specific people viewed your profile picture, that would be a massive privacy violation. Imagine if a stalker could instantly see if you viewed their photo. The feature would be weaponized.
There are several reasons why you might want to use the Facebook profile picture viewer URL: facebook profile picture viewer url
This is a common sub-query: "Facebook profile picture viewer url for old photos." The General Data Protection Regulation (GDPR) in Europe
