Get hot reloading working again

mosfet/protocol/modern.py

@@ -1,5 +1,6 @@
 """Chat adapter for the Minecraft 26.3 play protocol."""
 import time
+from contextlib import nullcontext
 
 from minecraft.networking.modern import (
     ChatCommand, ClientboundPlayerChatPacket, ServerboundChatPacket, SystemChat,
@@ -21,11 +22,13 @@ class ModernChatManager:
         text = '{}: {}'.format(sender, packet.message)
         print('[chat] {}: {}'.format(sender, packet.message), flush=True)
         if self.handler:
-            self.handler(('CHAT', sender, text))
+            with self.g.get('reload_lock') or nullcontext():
+                self.handler(('CHAT', sender, text))
 
     def handle_system_chat(self, packet, message):
         if self.handler:
-            self.handler(('SYSTEM', None, message))
+            with self.g.get('reload_lock') or nullcontext():
+                self.handler(('SYSTEM', None, message))
 
     def send(self, message):
         if not message: