chore: session owner promotion and connection approved updates

com.unity.netcode.gameobjects/CHANGELOG.md

@@ -16,6 +16,7 @@ Additional documentation and release notes are available at [Multiplayer Documen
 - The `NetworkManager` functions `GetTransportIdFromClientId` and `GetClientIdFromTransportId` will now return `ulong.MaxValue` when the clientId or transportId do not exist. (#3707)
 - Improved performance of the NetworkVariable. (#3683)
 - Improved performance around the NetworkBehaviour component. (#3687)
+- The first session owner no longer sends two synchronization messages to the service. (#3563)
 
 ### Deprecated
 

com.unity.netcode.gameobjects/Runtime/Core/NetworkManager.cs

@@ -241,7 +241,11 @@ internal void SetSessionOwner(ulong sessionOwner)
             OnSessionOwnerPromoted?.Invoke(sessionOwner);
         }
 
+#if ENABLE_SESSIONOWNER_PROMOTION_NOTIFICATION
+        public void PromoteSessionOwner(ulong clientId)
+#else
         internal void PromoteSessionOwner(ulong clientId)
+#endif
         {
             if (!DistributedAuthorityMode)
             {
@@ -258,10 +262,18 @@ internal void PromoteSessionOwner(ulong clientId)
             {
                 SessionOwner = clientId,
             };
-            var clients = ConnectionManager.ConnectedClientIds.Where(c => c != LocalClientId).ToArray();
-            foreach (var targetClient in clients)
+
+            if (CMBServiceConnection)
+            {
+                ConnectionManager.SendMessage(ref sessionOwnerMessage, NetworkDelivery.ReliableSequenced, ServerClientId);
+            }
+            else
             {
-                ConnectionManager.SendMessage(ref sessionOwnerMessage, NetworkDelivery.ReliableSequenced, targetClient);
+                var clients = ConnectionManager.ConnectedClientIds.Where(c => c != LocalClientId).ToArray();
+                foreach (var targetClient in clients)
+                {
+                    ConnectionManager.SendMessage(ref sessionOwnerMessage, NetworkDelivery.ReliableSequenced, targetClient);
+                }
             }
         }
 

com.unity.netcode.gameobjects/Runtime/Messaging/Messages/ConnectionApprovedMessage.cs

@@ -373,21 +373,18 @@ public void Handle(ref NetworkContext context)
 
                     if (!networkManager.SceneManager.IsRestoringSession)
                     {
-                        // Synchronize the service with the initial session owner's loaded scenes and spawned objects
-                        networkManager.SceneManager.SynchronizeNetworkObjects(NetworkManager.ServerClientId, true);
-
                         // Spawn any in-scene placed NetworkObjects
                         networkManager.SpawnManager.ServerSpawnSceneObjectsOnStartSweep();
 
+                        // Synchronize the service with the initial session owner's loaded scenes and spawned objects
+                        networkManager.SceneManager.SynchronizeNetworkObjects(NetworkManager.ServerClientId, true);
+
                         // Spawn the local player of the session owner
                         if (networkManager.AutoSpawnPlayerPrefabClientSide)
                         {
                             networkManager.ConnectionManager.CreateAndSpawnPlayer(OwnerClientId);
                         }
 
-                        // Synchronize the service with the initial session owner's loaded scenes and spawned objects
-                        networkManager.SceneManager.SynchronizeNetworkObjects(NetworkManager.ServerClientId, true);
-
                         // With scene management enabled and since the session owner doesn't send a scene event synchronize to itself,
                         // we need to notify the session owner that everything should be synchronized/spawned at this time.
                         networkManager.SpawnManager.NotifyNetworkObjectsSynchronized();