From 5a5165e89f3ed518f954c7f07c0eed9015acec9b Mon Sep 17 00:00:00 2001
From: Anon <bgteam@live.com>
Date: Tue, 7 Apr 2026 17:00:01 +0200
Subject: [PATCH] Fixed a non-existant configuration packet from crashing the
 client.

---
 MinecraftClient/Protocol/Handlers/Protocol18.cs | 14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/MinecraftClient/Protocol/Handlers/Protocol18.cs b/MinecraftClient/Protocol/Handlers/Protocol18.cs
index f63d9f77..9edf18ab 100644
--- a/MinecraftClient/Protocol/Handlers/Protocol18.cs
+++ b/MinecraftClient/Protocol/Handlers/Protocol18.cs
@@ -467,7 +467,19 @@ namespace MinecraftClient.Protocol.Handlers
 
                     // https://wiki.vg/Protocol#Configuration
                     case CurrentState.Configuration:
-                        switch (packetPalette.GetIncomingConfigurationTypeById(packetId))
+                        if (!packetPalette.GetMappingInConfiguration().TryGetValue(packetId, out var configurationPacketType))
+                        {
+                            if (packetPalette.GetMappingIn().ContainsKey(packetId))
+                            {
+                                currentState = CurrentState.Play;
+                                return HandlePlayPackets(packetId, packetData);
+                            }
+
+                            throw new KeyNotFoundException("Configuration Packet ID of 0x" + packetId.ToString("X2") +
+                                                           " doesn't exist!");
+                        }
+
+                        switch (configurationPacketType)
                         {
                             case ConfigurationPacketTypesIn.CookieRequest:
                                 var cookieName = dataTypes.ReadNextString(packetData);