Profile Viewer [work]: Anonymous Facebook

"Anonymous Facebook profile viewers" are scams and do not work.

There is no legitimate software or browser extension that can reveal who has viewed your Facebook profile or allow you to bypass privacy settings to view others' profiles secretly. The Verdict: Stay Away

If you tell me more about your goal, I can help further

If you're interested in keeping your own profile hidden, you can manage your privacy settings to control who sees your posts or use the Facebook "View As" tool to see what your profile looks like to the public. : Are you trying to secure your own profile from strangers? anonymous facebook profile viewer

Spam:

Some apps gain permission to post on your behalf, tagging your friends in advertisements for the scam. "Anonymous Facebook profile viewers" are scams and do

The Human Verification Ruse:

A common variation of the scam asks the user to complete a "human verification" process—usually taking a survey, downloading a game, or signing up for a subscription service—to prove they aren't a bot. This is affiliate fraud. The scammers get paid for your click, and you get nothing but a wasted afternoon and potentially a fraudulent charge on your credit card. : Are you trying to secure your own profile from strangers

If you want to ensure your profile stays private from "anonymous" lurkers: Lock Your Profile: