Security Notice: If you use a version 0.16.X version, update immediately to 0.16.5+ or disable the change password command. 0.16.X fixed this security bug. Older versions of 0.16.X are not affected.
A Sponge minecraft server plugin for second authentication. It has a built-in
Do you want to let your players protect their account (from hackers/login stealers) and keep playing while the session server is down. You can use this little plugin. You can protect your account with a password you choose or with a time based password created from a secret key, generated just for you.
TOTP Key generation (/register)
Android App Google Authenticator (IOS App exists too)
You can see there a time generated code which can be used for the login process. (/login
Additionally it display your user account name and the server ip.