There is any way to dispay Head Icons in Tab-List, when server is in offline-mode?
I found a great plugin - Auto-IN. When your server is in offline mode - premium users have PREMIUM, real UUID.
There is any way to add this to spigot, cause plugin have some bugs.
When you are login to server with Premium acc - u have Prem uuid and CAN see head Icons, even if server is in offline-mode. But if u are using cracked launcher - plugin detect it, that u are not premium. And u cant login with error (Invalid Session)
If u are log-in with cracked MC, using non-premium nickname (without skin) - u can login with that plugin installed.
So:
1. Add Head Icons to offline-mode server
2. add Prem-UUID in offline-mode server
3. add API to catch kick reason and send another to client.! - with that Plugin creator can catch reason (Invalid Session) and add player to exception list. Than send message (try to log-in again, u are in whitelist now)