Plugins such as healthbar that can now display information in the NamePlate of a user act extremely weird. Say server 1 added a plugin to manipulate the nameplate to display specific information, and server 2 did not add this plugin, and both plugins are connected with BungeeCord and Spigot. If your client registers information from a user's nameplate on server 1 and then goes on server 2 he will still register information on user's nameplates even though that server doesn't have the plugin. The information will be inaccurate but it will still display unless fully logged out. Also if the user returns back from server 2 to server 1 his client will crash. Don't exactly know if there is something Spigot / BungeeCord could do to maybe check and disable the client from receiving that information on Namplates on first join of a server.