To require a One-time password (Two-factor authentication) for logging to Adminer:
adminer-plugins/
.<?php // adminer-plugins.php
return array(
new AdminerLoginOtp(base64_decode('TFBq8DOR4s3L+w==')),
);
Note: The unique secret was randomly generated on this server (and not stored anywhere). You might want to generate the secret and the QR code without using third-party, e.g. with a library or simple functions.