After the Cambridge Analytica scandal, Facebook hardened its privacy protocols. Tracking who views a profile would be a massive privacy violation in Europe under GDPR and in California under CCPA. If Facebook secretly kept a log of every profile viewer, they would be legally obligated to disclose that data. They do not keep that log.
: Most "viewers" ask for your Facebook credentials to "verify" you, which allows scammers to hijack your actual account. facebook profile viewer no account verified
If you downloaded any "viewer" software, run a full antivirus scan (Malwarebytes or Windows Defender). After the Cambridge Analytica scandal, Facebook hardened its
