Fixed Scoreboard for Minecraft v.13.x Bukkit

    public <CraftPlayer> void sendTablistHeaderAndFooter(Player p, String header, String footer) {
        if(header == null) header = "";
        if(footer == null) footer = "";
     
        IChatBaseComponent tabHeader = ChatSerializer.a("{\"text\":\"" + header + "\"}");
        IChatBaseComponent tabFooter = ChatSerializer.a("{\"text\":\"" + footer + "\"}");
     
        PacketPlayOutPlayerListHeaderFooter headerPacket = new PacketPlayOutPlayerListHeaderFooter();
        PacketPlayOutPlayerListHeaderFooter footerPacket = new PacketPlayOutPlayerListHeaderFooter();
        try {
            Field[] header1 = headerPacket.getClass().getDeclaredFields();
            header1[0].setAccessible(true);
            header1[0].set(headerPacket, tabHeader);
         
            Field[] header2 = headerPacket.getClass().getDeclaredFields();
            header2[1].setAccessible(true);
            header2[1].set(headerPacket, tabFooter);
         
            ((org.bukkit.craftbukkit.v1_13_R2.entity.CraftPlayer)p).getHandle().playerConnection.sendPacket(headerPacket);
         
            Field[] header3 = footerPacket.getClass().getDeclaredFields();
            header3[0].setAccessible(true);
            header3[0].set(footerPacket, tabHeader);
         
            Field[] header4 = footerPacket.getClass().getDeclaredFields();
            header4[1].setAccessible(true);
            header4[1].set(footerPacket, tabHeader);
         
            ((org.bukkit.craftbukkit.v1_13_R2.entity.CraftPlayer)p).getHandle().playerConnection.sendPacket(headerPacket);
            // ((org.bukkit.craftbukkit.v1_13_R2.entity.CraftPlayer)p).getHandle().playerConnection.sendPacket(footerPacket);
        } catch(Exception e) {
            e.printStackTrace();
        }finally{
        }
    }
}