I noticet that if I'm connected to my server with RCon and try to stop the game server it never stops and spills in the server log bunch of errors. I expected server to stop gracefully and rcon connection to be disconnected instead.
To reproduce i started Spigot without any plugins and connected to it with mcrcon. When i try to stop the server it never stops. When i exit mcrcon client server manages to stop.
Attached you can find logs from both vanilla and spigot 1.14.4