Facebook actually has a public directory of users. Some ethical hackers and researchers have crawled this data to create wordlists for password security testing.
Facebook has a built-in tool: and Password Leak Detection . Facebook will notify you if your password matches a leaked credential set (without revealing the leak source). index of passwordtxt facebook exclusive
If you're trying to , you can find it securely in your browser's Password Manager or by using Facebook's official recovery tools . Facebook actually has a public directory of users