Server Teleportation Issue

So I see this is happening on most new servers, and am wondering how to fix this. Whenever I teleport to another world on new servers, usually numbers (such as 1497491514680) pop up on the screen with nothing else that gives me a hint how to stop it. It shows it for all other players on the servers, and I do not know if a plugin is causing this. It would be great if someone could identify the problem and provide instructions for how to fix it. Thanks!