fix: closes #716

server.py

@@ -48,8 +48,11 @@ async def broadcast_handler(websocket: websockets.WebSocketServerProtocol):
                 pass
 
             # Broadcast to all OTHER clients
+            if not clients:
+                continue
+                
             disconnected = set()
-            # Create broadcast tasks paired with their target client
+            # Create broadcast tasks, tracking which client each task targets
             task_client_pairs = []
             for client in clients:
                 if client != websocket and client.open:
@@ -57,12 +60,13 @@ async def broadcast_handler(websocket: websockets.WebSocketServerProtocol):
                     task_client_pairs.append((task, client))
 
             if task_client_pairs:
-                tasks = [t for t, _ in task_client_pairs]
+                tasks = [pair[0] for pair in task_client_pairs]
                 results = await asyncio.gather(*tasks, return_exceptions=True)
-                for (task, client), result in zip(task_client_pairs, results):
+                for i, result in enumerate(results):
                     if isinstance(result, Exception):
-                        logger.error(f"Failed to send to a client {client.remote_address}: {result}")
-                        disconnected.add(client)
+                        target_client = task_client_pairs[i][1]
+                        logger.error(f"Failed to send to client {target_client.remote_address}: {result}")
+                        disconnected.add(target_client)
             
             if disconnected:
                 clients.difference_update(disconnected)