[CRASH] Unable to get into Fabric Server running v0.6.3-1.20.6

[NeverBeggarX]

Version information

itemswapper-fabric-0.6.3-mc1.20.6

Other mods installed

fabric-api-0.98.0+1.20.6

Reproduction Steps

Installing itemswapper-fabric-0.6.3-mc1.20.6 to server, players are completely unable to join the server, including localhost. Works when only installed on the Client, but when trying to integrate to Fabric Server, does not let players join.

Crash Report file

Client Side Report

Server Side Report
[18:56:54] [Server thread/INFO]: NeverBeggar[/127.0.0.1:62953] logged in with entity id 8 at (-271.37408161820616, 56.0, 25.191293546297032)
[18:56:54] [Server thread/INFO]: [voicechat] Using Fabric Permissions API
[18:56:54] [Server thread/INFO]: NeverBeggar joined the game
[18:56:54] [Netty Server IO #2/ERROR]: Error sending packet clientbound/minecraft:custom_payload
io.netty.handler.codec.EncoderException: Failed to encode packet 'clientbound/minecraft:custom_payload' (itemswapper:enableshulker)
at net.minecraft.class_9136.handler$zek000$fabric-networking-api-v1$encode(class_9136.java:547) ~[server-intermediary.jar:?]
at net.minecraft.class_9136.method_56426(class_9136.java:55) ~[server-intermediary.jar:?]
at net.minecraft.class_9136.encode(class_9136.java:14) ~[server-intermediary.jar:?]
at net.minecraft.class_2545.method_10838(class_2545.java:26) ~[server-intermediary.jar:?]
at net.minecraft.class_2545.encode(class_2545.java:12) ~[server-intermediary.jar:?]
at io.netty.handler.codec.MessageToByteEncoder.write(MessageToByteEncoder.java:107) ~[netty-codec-4.1.97.Final.jar:?]
at io.netty.channel.AbstractChannelHandlerContext.invokeWrite0(AbstractChannelHandlerContext.java:881) ~[netty-transport-4.1.97.Final.jar:?]
at io.netty.channel.AbstractChannelHandlerContext.invokeWrite(AbstractChannelHandlerContext.java:863) ~[netty-transport-4.1.97.Final.jar:?]
at io.netty.channel.AbstractChannelHandlerContext.write(AbstractChannelHandlerContext.java:968) ~[netty-transport-4.1.97.Final.jar:?]
at io.netty.channel.AbstractChannelHandlerContext.write(AbstractChannelHandlerContext.java:856) ~[netty-transport-4.1.97.Final.jar:?]
at io.netty.handler.codec.MessageToMessageEncoder.write(MessageToMessageEncoder.java:113) ~[netty-codec-4.1.97.Final.jar:?]
at io.netty.channel.AbstractChannelHandlerContext.invokeWrite0(AbstractChannelHandlerContext.java:881) ~[netty-transport-4.1.97.Final.jar:?]
at io.netty.channel.AbstractChannelHandlerContext.invokeWrite(AbstractChannelHandlerContext.java:863) ~[netty-transport-4.1.97.Final.jar:?]
at io.netty.channel.AbstractChannelHandlerContext.write(AbstractChannelHandlerContext.java:968) ~[netty-transport-4.1.97.Final.jar:?]
at io.netty.channel.AbstractChannelHandlerContext.write(AbstractChannelHandlerContext.java:856) ~[netty-transport-4.1.97.Final.jar:?]
at io.netty.channel.ChannelOutboundHandlerAdapter.write(ChannelOutboundHandlerAdapter.java:113) ~[netty-transport-4.1.97.Final.jar:?]
at net.minecraft.class_2535$2.write(class_2535.java:518) ~[server-intermediary.jar:?]
at io.netty.channel.AbstractChannelHandlerContext.invokeWrite0(AbstractChannelHandlerContext.java:881) ~[netty-transport-4.1.97.Final.jar:?]
at io.netty.channel.AbstractChannelHandlerContext.invokeWriteAndFlush(AbstractChannelHandlerContext.java:940) ~[netty-transport-4.1.97.Final.jar:?]
at io.netty.channel.AbstractChannelHandlerContext.write(AbstractChannelHandlerContext.java:966) ~[netty-transport-4.1.97.Final.jar:?]
at io.netty.channel.AbstractChannelHandlerContext.writeAndFlush(AbstractChannelHandlerContext.java:934) ~[netty-transport-4.1.97.Final.jar:?]
at io.netty.channel.AbstractChannelHandlerContext.writeAndFlush(AbstractChannelHandlerContext.java:984) ~[netty-transport-4.1.97.Final.jar:?]
at io.netty.channel.DefaultChannelPipeline.writeAndFlush(DefaultChannelPipeline.java:1025) ~[netty-transport-4.1.97.Final.jar:?]
at io.netty.channel.AbstractChannel.writeAndFlush(AbstractChannel.java:306) ~[netty-transport-4.1.97.Final.jar:?]
at net.minecraft.class_2535.method_36942(class_2535.java:342) ~[server-intermediary.jar:?]
at net.minecraft.class_2535.method_52917(class_2535.java:337) ~[server-intermediary.jar:?]
at io.netty.util.concurrent.AbstractEventExecutor.runTask(AbstractEventExecutor.java:174) ~[netty-common-4.1.97.Final.jar:?]
at io.netty.util.concurrent.AbstractEventExecutor.safeExecute(AbstractEventExecutor.java:167) ~[netty-common-4.1.97.Final.jar:?]
at io.netty.util.concurrent.SingleThreadEventExecutor.runAllTasks(SingleThreadEventExecutor.java:470) ~[netty-common-4.1.97.Final.jar:?]
at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:569) ~[netty-transport-4.1.97.Final.jar:?]
at io.netty.util.concurrent.SingleThreadEventExecutor$4.run(SingleThreadEventExecutor.java:997) ~[netty-common-4.1.97.Final.jar:?]
at io.netty.util.internal.ThreadExecutorMap$2.run(ThreadExecutorMap.java:74) ~[netty-common-4.1.97.Final.jar:?]
at java.base/java.lang.Thread.run(Thread.java:1570) [?:?]
Caused by: java.lang.ClassCastException: class dev.tr7zw.itemswapper.packets.ShulkerSupportPayload cannot be cast to class net.minecraft.class_8711 (dev.tr7zw.itemswapper.packets.ShulkerSupportPayload and net.minecraft.class_8711 are in unnamed module of loader net.fabricmc.loader.impl.launch.knot.KnotClassLoader @c038203)
at net.minecraft.class_9139$6.encode(class_9139.java:42) ~[server-intermediary.jar:?]
at net.minecraft.class_8710$1.method_56489(class_8710.java:52) ~[server-intermediary.jar:?]
at net.minecraft.class_8710$1.method_56490(class_8710.java:57) ~[server-intermediary.jar:?]
at net.minecraft.class_8710$1.encode(class_8710.java:39) ~[server-intermediary.jar:?]
at net.minecraft.class_9139$8.encode(class_9139.java:81) ~[server-intermediary.jar:?]
at net.minecraft.class_9139$9.method_56442(class_9139.java:97) ~[server-intermediary.jar:?]
at net.minecraft.class_9139$9.encode(class_9139.java:87) ~[server-intermediary.jar:?]
at net.minecraft.class_9136.method_56426(class_9136.java:53) ~[server-intermediary.jar:?]
... 31 more
[18:56:54] [Netty Server IO #2/ERROR]: Error sending packet clientbound/minecraft:custom_payload
io.netty.handler.codec.EncoderException: Failed to encode packet 'clientbound/minecraft:custom_payload' (itemswapper:enablerefill)
at net.minecraft.class_9136.handler$zek000$fabric-networking-api-v1$encode(class_9136.java:547) ~[server-intermediary.jar:?]
at net.minecraft.class_9136.method_56426(class_9136.java:55) ~[server-intermediary.jar:?]
at net.minecraft.class_9136.encode(class_9136.java:14) ~[server-intermediary.jar:?]
at net.minecraft.class_2545.method_10838(class_2545.java:26) ~[server-intermediary.jar:?]
at net.minecraft.class_2545.encode(class_2545.java:12) ~[server-intermediary.jar:?]
at io.netty.handler.codec.MessageToByteEncoder.write(MessageToByteEncoder.java:107) ~[netty-codec-4.1.97.Final.jar:?]
at io.netty.channel.AbstractChannelHandlerContext.invokeWrite0(AbstractChannelHandlerContext.java:881) ~[netty-transport-4.1.97.Final.jar:?]
at io.netty.channel.AbstractChannelHandlerContext.invokeWrite(AbstractChannelHandlerContext.java:863) ~[netty-transport-4.1.97.Final.jar:?]
at io.netty.channel.AbstractChannelHandlerContext.write(AbstractChannelHandlerContext.java:968) ~[netty-transport-4.1.97.Final.jar:?]
at io.netty.channel.AbstractChannelHandlerContext.write(AbstractChannelHandlerContext.java:856) ~[netty-transport-4.1.97.Final.jar:?]
at io.netty.handler.codec.MessageToMessageEncoder.write(MessageToMessageEncoder.java:113) ~[netty-codec-4.1.97.Final.jar:?]
at io.netty.channel.AbstractChannelHandlerContext.invokeWrite0(AbstractChannelHandlerContext.java:881) ~[netty-transport-4.1.97.Final.jar:?]
at io.netty.channel.AbstractChannelHandlerContext.invokeWrite(AbstractChannelHandlerContext.java:863) ~[netty-transport-4.1.97.Final.jar:?]
at io.netty.channel.AbstractChannelHandlerContext.write(AbstractChannelHandlerContext.java:968) ~[netty-transport-4.1.97.Final.jar:?]
at io.netty.channel.AbstractChannelHandlerContext.write(AbstractChannelHandlerContext.java:856) ~[netty-transport-4.1.97.Final.jar:?]
at io.netty.channel.ChannelOutboundHandlerAdapter.write(ChannelOutboundHandlerAdapter.java:113) ~[netty-transport-4.1.97.Final.jar:?]
at net.minecraft.class_2535$2.write(class_2535.java:518) ~[server-intermediary.jar:?]
at io.netty.channel.AbstractChannelHandlerContext.invokeWrite0(AbstractChannelHandlerContext.java:881) ~[netty-transport-4.1.97.Final.jar:?]
at io.netty.channel.AbstractChannelHandlerContext.invokeWriteAndFlush(AbstractChannelHandlerContext.java:940) ~[netty-transport-4.1.97.Final.jar:?]
at io.netty.channel.AbstractChannelHandlerContext.write(AbstractChannelHandlerContext.java:966) ~[netty-transport-4.1.97.Final.jar:?]
at io.netty.channel.AbstractChannelHandlerContext.writeAndFlush(AbstractChannelHandlerContext.java:934) ~[netty-transport-4.1.97.Final.jar:?]
at io.netty.channel.AbstractChannelHandlerContext.writeAndFlush(AbstractChannelHandlerContext.java:984) ~[netty-transport-4.1.97.Final.jar:?]
at io.netty.channel.DefaultChannelPipeline.writeAndFlush(DefaultChannelPipeline.java:1025) ~[netty-transport-4.1.97.Final.jar:?]
at io.netty.channel.AbstractChannel.writeAndFlush(AbstractChannel.java:306) ~[netty-transport-4.1.97.Final.jar:?]
at net.minecraft.class_2535.method_36942(class_2535.java:342) ~[server-intermediary.jar:?]
at net.minecraft.class_2535.method_52917(class_2535.java:337) ~[server-intermediary.jar:?]
at io.netty.util.concurrent.AbstractEventExecutor.runTask(AbstractEventExecutor.java:174) ~[netty-common-4.1.97.Final.jar:?]
at io.netty.util.concurrent.AbstractEventExecutor.safeExecute(AbstractEventExecutor.java:167) ~[netty-common-4.1.97.Final.jar:?]
at io.netty.util.concurrent.SingleThreadEventExecutor.runAllTasks(SingleThreadEventExecutor.java:470) ~[netty-common-4.1.97.Final.jar:?]
at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:569) ~[netty-transport-4.1.97.Final.jar:?]
at io.netty.util.concurrent.SingleThreadEventExecutor$4.run(SingleThreadEventExecutor.java:997) ~[netty-common-4.1.97.Final.jar:?]
at io.netty.util.internal.ThreadExecutorMap$2.run(ThreadExecutorMap.java:74) ~[netty-common-4.1.97.Final.jar:?]
at java.base/java.lang.Thread.run(Thread.java:1570) [?:?]
Caused by: java.lang.ClassCastException: class dev.tr7zw.itemswapper.packets.RefillSupportPayload cannot be cast to class net.minecraft.class_8711 (dev.tr7zw.itemswapper.packets.RefillSupportPayload and net.minecraft.class_8711 are in unnamed module of loader net.fabricmc.loader.impl.launch.knot.KnotClassLoader @c038203)
at net.minecraft.class_9139$6.encode(class_9139.java:42) ~[server-intermediary.jar:?]
at net.minecraft.class_8710$1.method_56489(class_8710.java:52) ~[server-intermediary.jar:?]
at net.minecraft.class_8710$1.method_56490(class_8710.java:57) ~[server-intermediary.jar:?]
at net.minecraft.class_8710$1.encode(class_8710.java:39) ~[server-intermediary.jar:?]
at net.minecraft.class_9139$8.encode(class_9139.java:81) ~[server-intermediary.jar:?]
at net.minecraft.class_9139$9.method_56442(class_9139.java:97) ~[server-intermediary.jar:?]
at net.minecraft.class_9139$9.encode(class_9139.java:87) ~[server-intermediary.jar:?]
at net.minecraft.class_9136.method_56426(class_9136.java:53) ~[server-intermediary.jar:?]
... 31 more
[18:56:55] [Server thread/INFO]: NeverBeggar lost connection: Internal Exception: io.netty.handler.codec.EncoderException: Failed to encode packet 'clientbound/minecraft:custom_payload' (itemswapper:enableshulker)
[18:56:55] [Server thread/INFO]: NeverBeggar left the game
[18:56:55] [Server thread/INFO]: [voicechat] Disconnecting client NeverBeggar
[18:56:55] [Server thread/WARN]: handleDisconnection() called twice

Client Image

Additional information

This is my first time running a Fabric Server, I just transferred this world from my paper server this morning, and just want to get features like refilling inventory from shulkers available to my players (and myself). If there's anything wrong I'm doing on my end please bonk me for being dumb.

[DarkShadowZX58]

Having same issue