Facebook explicitly states they do not let people track profile viewers.
Facebook’s direction is , not less. Any future "viewer" will have to be explicitly authorized by the user whose picture is being viewed.
: Common user complaints include the tool opening a console full of errors or, more seriously, causing the user to be logged out of Facebook automatically after use. Critical Pros and Cons Pros Cons
If you cannot see someone’s profile picture because they set it to "Friends Only," respect that boundary. Facebook provides that control for a reason.
Press came—not the shrill condemnation, but measured interest. A podcast interviewed Jaya about designing tools that respect social norms. She spoke plainly about tradeoffs: transparency, intent, and the small friction that could turn a blunt instrument into a mindful connector. She told a story about the woman with the tattoo who later wrote to thank her for forcing a pause—"I wasn’t ready to tell that story," she wrote; "your delay gave me a chance to decide how."