• This issue is not solved in a development build

Describe the bug
A clear and concise description of what the bug is.

The moment a Player joins, and starts sending packets to the Server as example by using my Skills or an Item in general, he immediately gets kicked off of the Server.

To Reproduce
Steps to reproduce the behavior:

1. Join Server
2. Choose Character
3. Use ability from hotkeys
4. get kicked instantly

Expected behavior
A clear and concise description of what you expected to happen.
Not to get kicked

Screenshots
If applicable, add screenshots to help explain your problem.

Version Info
Provide your ProtocolLib install info with /protocol dump through pastebin.

dump-2023-11-21_17.12.15.txt

Additional context
Add any other context about the problem here.

errorcode:

logged in with entity id 328 at ([world]5218.5, 45.0, 5193.5)
[16:05:16] [Netty Epoll Server IO #1/ERROR]: Packet encoding of packet ClientboundSetEntityDataPacket (ID: 84) threw (skippable? false)
java.lang.ClassCastException: class net.minecraft.network.syncher.DataWatcher$Item cannot be cast to class net.minecraft.network.syncher.DataWatcher$b (net.minecraft.network.syncher.DataWatcher$Item and net.minecraft.network.syncher.DataWatcher$b are in unnamed module of loader java.net.URLClassLoader @66cd51c3)
at net.minecraft.network.protocol.game.ClientboundSetEntityDataPacket.pack(ClientboundSetEntityDataPacket.java:17) ~[?:?]
at net.minecraft.network.protocol.game.ClientboundSetEntityDataPacket.write(ClientboundSetEntityDataPacket.java:38) ~[?:?]
at net.minecraft.network.PacketEncoder.encode(PacketEncoder.java:42) ~[paper-1.20.2.jar:git-Paper-297]
at net.minecraft.network.PacketEncoder.encode(PacketEncoder.java:14) ~[paper-1.20.2.jar:git-Paper-297]
at io.netty.handler.codec.MessageToByteEncoder.write(MessageToByteEncoder.java:107) ~[netty-codec-4.1.97.Final.jar:4.1.97.Final]
at io.netty.channel.AbstractChannelHandlerContext.invokeWrite0(AbstractChannelHandlerContext.java:881) ~[netty-transport-4.1.97.Final.jar:4.1.97.Final]
at io.netty.channel.AbstractChannelHandlerContext.invokeWrite(AbstractChannelHandlerContext.java:863) ~[netty-transport-4.1.97.Final.jar:4.1.97.Final]
at io.netty.channel.AbstractChannelHandlerContext.write(AbstractChannelHandlerContext.java:968) ~[netty-transport-4.1.97.Final.jar:4.1.97.Final]
at io.netty.channel.AbstractChannelHandlerContext.write(AbstractChannelHandlerContext.java:856) ~[netty-transport-4.1.97.Final.jar:4.1.97.Final]
at io.netty.handler.codec.MessageToByteEncoder.write(MessageToByteEncoder.java:120) ~[netty-codec-4.1.97.Final.jar:4.1.97.Final]
at io.netty.channel.AbstractChannelHandlerContext.invokeWrite0(AbstractChannelHandlerContext.java:881) ~[netty-transport-4.1.97.Final.jar:4.1.97.Final]
at io.netty.channel.AbstractChannelHandlerContext.invokeWrite(AbstractChannelHandlerContext.java:863) ~[netty-transport-4.1.97.Final.jar:4.1.97.Final]
at io.netty.channel.AbstractChannelHandlerContext.write(AbstractChannelHandlerContext.java:968) ~[netty-transport-4.1.97.Final.jar:4.1.97.Final]
at io.netty.channel.AbstractChannelHandlerContext.write(AbstractChannelHandlerContext.java:856) ~[netty-transport-4.1.97.Final.jar:4.1.97.Final]
at io.netty.handler.codec.MessageToMessageEncoder.write(MessageToMessageEncoder.java:113) ~[netty-codec-4.1.97.Final.jar:4.1.97.Final]
at io.netty.channel.AbstractChannelHandlerContext.invokeWrite0(AbstractChannelHandlerContext.java:881) ~[netty-transport-4.1.97.Final.jar:4.1.97.Final]
at io.netty.channel.AbstractChannelHandlerContext.invokeWrite(AbstractChannelHandlerContext.java:863) ~[netty-transport-4.1.97.Final.jar:4.1.97.Final]
at io.netty.channel.AbstractChannelHandlerContext.write(AbstractChannelHandlerContext.java:968) ~[netty-transport-4.1.97.Final.jar:4.1.97.Final]
at io.netty.channel.AbstractChannelHandlerContext.write(AbstractChannelHandlerContext.java:856) ~[netty-transport-4.1.97.Final.jar:4.1.97.Final]
at io.netty.channel.ChannelDuplexHandler.write(ChannelDuplexHandler.java:115) ~[netty-transport-4.1.97.Final.jar:4.1.97.Final]
at com.ticxo.modelengine.v1_20_R2.network.ModelEngineChannelHandler.write(ModelEngineChannelHandler.java:110) ~[ModelEngine-4.0.3 (1).jar:?]
at io.netty.channel.AbstractChannelHandlerContext.invokeWrite0(AbstractChannelHandlerContext.java:879) ~[netty-transport-4.1.97.Final.jar:4.1.97.Final]
at io.netty.channel.AbstractChannelHandlerContext.invokeWrite(AbstractChannelHandlerContext.java:863) ~[netty-transport-4.1.97.Final.jar:4.1.97.Final]
at io.netty.channel.AbstractChannelHandlerContext.write(AbstractChannelHandlerContext.java:968) ~[netty-transport-4.1.97.Final.jar:4.1.97.Final]
at io.netty.channel.AbstractChannelHandlerContext.write(AbstractChannelHandlerContext.java:856) ~[netty-transport-4.1.97.Final.jar:4.1.97.Final]
at io.netty.channel.ChannelDuplexHandler.write(ChannelDuplexHandler.java:115) ~[netty-transport-4.1.97.Final.jar:4.1.97.Final]
at io.lumine.mythic.core.volatilecode.v1_20_R2.packets.VolatileChannelHandler.write(VolatileChannelHandler.java:65) ~[MythicMobs-5.4.1.jar:?]
at io.netty.channel.AbstractChannelHandlerContext.invokeWrite0(AbstractChannelHandlerContext.java:879) ~[netty-transport-4.1.97.Final.jar:4.1.97.Final]
at io.netty.channel.AbstractChannelHandlerContext.invokeWrite(AbstractChannelHandlerContext.java:863) ~[netty-transport-4.1.97.Final.jar:4.1.97.Final]
at io.netty.channel.AbstractChannelHandlerContext.write(AbstractChannelHandlerContext.java:968) ~[netty-transport-4.1.97.Final.jar:4.1.97.Final]
at io.netty.channel.AbstractChannelHandlerContext.write(AbstractChannelHandlerContext.java:856) ~[netty-transport-4.1.97.Final.jar:4.1.97.Final]
at io.netty.channel.DefaultChannelPipeline.write(DefaultChannelPipeline.java:1015) ~[netty-transport-4.1.97.Final.jar:4.1.97.Final]
at io.netty.channel.AbstractChannel.write(AbstractChannel.java:301) ~[netty-transport-4.1.97.Final.jar:4.1.97.Final]
at com.comphenix.protocol.injector.netty.channel.NettyChannelProxy.write(NettyChannelProxy.java:210) ~[ProtocolLib.jar:?]
at com.comphenix.protocol.injector.netty.channel.NettyChannelProxy.write(NettyChannelProxy.java:199) ~[ProtocolLib.jar:?]
at net.minecraft.network.Connection.doSendPacket(Connection.java:448) ~[?:?]
at net.minecraft.network.Connection.lambda$sendPacket$10(Connection.java:433) ~[?:?]
at com.comphenix.protocol.injector.netty.channel.NettyEventLoopProxy.lambda$proxyRunnable$2(NettyEventLoopProxy.java:48) ~[ProtocolLib.jar:?]
at io.netty.util.concurrent.AbstractEventExecutor.runTask(AbstractEventExecutor.java:174) ~[netty-common-4.1.97.Final.jar:4.1.97.Final]
at io.netty.util.concurrent.AbstractEventExecutor.safeExecute(AbstractEventExecutor.java:167) ~[netty-common-4.1.97.Final.jar:4.1.97.Final]
at io.netty.util.concurrent.SingleThreadEventExecutor.runAllTasks(SingleThreadEventExecutor.java:470) ~[netty-common-4.1.97.Final.jar:4.1.97.Final]
at io.netty.channel.epoll.EpollEventLoop.run(EpollEventLoop.java:413) ~[netty-transport-classes-epoll-4.1.97.Final.jar:4.1.97.Final]
at io.netty.util.concurrent.SingleThreadEventExecutor$4.run(SingleThreadEventExecutor.java:997) ~[netty-common-4.1.97.Final.jar:4.1.97.Final]
at io.netty.util.internal.ThreadExecutorMap$2.run(ThreadExecutorMap.java:74) ~[netty-common-4.1.97.Final.jar:4.1.97.Final]
at java.lang.Thread.run(Thread.java:840) ~[?:?]
[16:05:16] [Server thread/INFO]: Derituson lost connection: Internal Exception: io.netty.handler.codec.EncoderException: java.lang.ClassCastException: class net.minecraft.network.syncher.DataWatcher$Item cannot be cast to class net.minecraft.network.syncher.DataWatcher$b (net.minecraft.network.syncher.DataWatcher$Item and net.minecraft.network.syncher.DataWatcher$b are in unnamed module of loader java.net.URLClassLoader @66cd51c3)
[16:05:16] [Server thread/INFO]: [GoA] Saving guardian with current character for player Derituson
[16:05:16] [Server thread/INFO]: Derituson left the game

Also happens in 1.20.1

Hi,

this is no issue with ProtocolLib itself. It is most likely caused by the plugin which adds some abilities to the hotbar that needs to be updated to the latest minecraft versions.

@lukalt Are you sure? I have the same problem when I try to teleport someone