Until yesterday you could choose some of your friends as trusted contacts, in case you lost access to your Facebook account.
The friends you could choose were able to send you one code recoverys with a special URL so you can log back into your account.
This until yesterday, because today the largest social network he said that it decided to abolish this function.
The help σελίδα mentions them
Trusted contacts will be removed shortly. This means that the friends you have selected will no longer be able to help you return to Facebook if you lose access to your account.
Make sure your email address and phone number are up to date account settings. You can also find more tips on how to keep your account safe.