--- a/net/minecraft/network/Connection.java
+++ b/net/minecraft/network/Connection.java
@@ -82,13 +82,13 @@
         marker.add(Connection.PACKET_MARKER);
     });
     public static final Supplier<NioEventLoopGroup> NETWORK_WORKER_GROUP = Suppliers.memoize(() -> {
-        return new NioEventLoopGroup(0, (new ThreadFactoryBuilder()).setNameFormat("Netty Client IO #%d").setDaemon(true).build());
+        return new NioEventLoopGroup(0, (new ThreadFactoryBuilder()).setNameFormat("Netty Client IO #%d").setDaemon(true).setUncaughtExceptionHandler(new net.minecraft.DefaultUncaughtExceptionHandlerWithName(LOGGER)).build()); // Paper
     });
     public static final Supplier<EpollEventLoopGroup> NETWORK_EPOLL_WORKER_GROUP = Suppliers.memoize(() -> {
-        return new EpollEventLoopGroup(0, (new ThreadFactoryBuilder()).setNameFormat("Netty Epoll Client IO #%d").setDaemon(true).build());
+        return new EpollEventLoopGroup(0, (new ThreadFactoryBuilder()).setNameFormat("Netty Epoll Client IO #%d").setDaemon(true).setUncaughtExceptionHandler(new net.minecraft.DefaultUncaughtExceptionHandlerWithName(LOGGER)).build()); // Paper
     });
     public static final Supplier<DefaultEventLoopGroup> LOCAL_WORKER_GROUP = Suppliers.memoize(() -> {
-        return new DefaultEventLoopGroup(0, (new ThreadFactoryBuilder()).setNameFormat("Netty Local Client IO #%d").setDaemon(true).build());
+        return new DefaultEventLoopGroup(0, (new ThreadFactoryBuilder()).setNameFormat("Netty Local Client IO #%d").setDaemon(true).setUncaughtExceptionHandler(new net.minecraft.DefaultUncaughtExceptionHandlerWithName(LOGGER)).build()); // Paper
     });
     private static final ProtocolInfo<ServerHandshakePacketListener> INITIAL_PROTOCOL = HandshakeProtocols.SERVERBOUND;
     private final PacketFlow receiving;
@@ -96,6 +96,11 @@
     private final Queue<Consumer<Connection>> pendingActions = Queues.newConcurrentLinkedQueue();
     public Channel channel;
     public SocketAddress address;
+    // Spigot Start
+    public java.util.UUID spoofedUUID;
+    public com.mojang.authlib.properties.Property[] spoofedProfile;
+    public boolean preparing = true;
+    // Spigot End
     @Nullable
     private volatile PacketListener disconnectListener;
     @Nullable
@@ -114,6 +119,19 @@
     private volatile DisconnectionDetails delayedDisconnect;
     @Nullable
     BandwidthDebugMonitor bandwidthDebugMonitor;
+    public String hostname = ""; // CraftBukkit - add field
+
+    // Paper start - add utility methods
+    public final net.minecraft.server.level.ServerPlayer getPlayer() {
+        if (this.packetListener instanceof net.minecraft.server.network.ServerGamePacketListenerImpl impl) {
+            return impl.player;
+        } else if (this.packetListener instanceof net.minecraft.server.network.ServerCommonPacketListenerImpl impl) {
+            org.bukkit.craftbukkit.entity.CraftPlayer player = impl.getCraftPlayer();
+            return player == null ? null : player.getHandle();
+        }
+        return null;
+    }
+    // Paper end - add utility methods
 
     public Connection(PacketFlow side) {
         this.receiving = side;
@@ -123,6 +141,9 @@
         super.channelActive(channelhandlercontext);
         this.channel = channelhandlercontext.channel();
         this.address = this.channel.remoteAddress();
+        // Spigot Start
+        this.preparing = false;
+        // Spigot End
         if (this.delayedDisconnect != null) {
             this.disconnect(this.delayedDisconnect);
         }
@@ -176,6 +197,7 @@
 
             }
         }
+        if (net.minecraft.server.MinecraftServer.getServer().isDebugging()) io.papermc.paper.util.TraceUtil.printStackTrace(throwable); // Spigot // Paper
     }
 
     protected void channelRead0(ChannelHandlerContext channelhandlercontext, Packet<?> packet) {
@@ -205,7 +227,7 @@
     }
 
     private static <T extends PacketListener> void genericsFtw(Packet<T> packet, PacketListener listener) {
-        packet.handle(listener);
+        packet.handle((T) listener); // CraftBukkit - decompile error
     }
 
     private void validateListener(ProtocolInfo<?> state, PacketListener listener) {
@@ -464,12 +486,15 @@
     }
 
     public void disconnect(DisconnectionDetails disconnectionInfo) {
+        // Spigot Start
+        this.preparing = false;
+        // Spigot End
         if (this.channel == null) {
             this.delayedDisconnect = disconnectionInfo;
         }
 
         if (this.isConnected()) {
-            this.channel.close().awaitUninterruptibly();
+            this.channel.close(); // We can't wait as this may be called from an event loop.
             this.disconnectionDetails = disconnectionInfo;
         }
 
@@ -537,7 +562,7 @@
     }
 
     public void configurePacketHandler(ChannelPipeline pipeline) {
-        pipeline.addLast("hackfix", new ChannelOutboundHandlerAdapter(this) {
+        pipeline.addLast("hackfix", new ChannelOutboundHandlerAdapter() { // CraftBukkit - decompile error
             public void write(ChannelHandlerContext channelhandlercontext, Object object, ChannelPromise channelpromise) throws Exception {
                 super.write(channelhandlercontext, object, channelpromise);
             }
@@ -661,6 +686,7 @@
 
                     packetlistener1.onDisconnect(disconnectiondetails);
                 }
+                this.pendingActions.clear(); // Free up packet queue.
 
             }
         }