This update fixes an issue affecting the platforms spigot and velocity in where they fail to call a TabCompleteEvent when a ServerboundCommandSuggestionPacket is sent requesting completions for a root command node.

Normally a client cannot request completions for a root node ever since the brigadier command system was implemented, but with a Modded client or by the use of ViaBackwards clients can send a request for completions for a root command node.

Not only does this bypass plugins listening for a TabCompleteEvent but also bypasses all permission checks for commands, allowing exposure of all commands to the client. (except for paper where it was partially fixed and won't TabComplete commands the player doesn't meet the internal requirements for)

This now requires ProtocolLib for Bukkit, and Protocolize for Velocity in order to block this exploit.