How do I block "/ + tab"?

You can't disable tab completion with bungeecord. It's only possible on spigot server.

Code (Text):

commands:
  tab-complete: -1

Set tab-complete to -1 to disable.

 

With code you can try TabCompleteEvent (https://ci.md-5.net/job/BungeeCord/...t/md_5/bungee/api/event/TabCompleteEvent.html) or TabCompleteResponseEvent (https://ci.md-5.net/job/BungeeCord/...ungee/api/event/TabCompleteResponseEvent.html)

 

also if you just want certain commands to be blocked, use the PlayerCommandSendEvent

Example:

Code (Text):

    @EventHandler
    public void onPlayerTab(PlayerCommandSendEvent e) {
        List<String> blockedCommands = new ArrayList<>();
        blockedCommands.add("gamemode");
        blockedCommands.add("pl");
        blockedCommands.add("plugins");
        e.getCommands().removeAll(blockedCommands);
    }

 

No. PlayerCommandSendEvent was a bukkit event back then in 1.8