"InvalidOperationException" and "ArgumentException" errors thrown in the Console when opening SampleScene after New Sub Scene is opened

InvalidOperationException: The previously scheduled job AsyncLoadSceneOperation:AsyncLoadSceneJob writes to the Unity.Entities.EntityManager AsyncLoadSceneJob.Transaction.m_Manager. You must call JobHandle.Complete() on the job AsyncLoadSceneOperation:AsyncLoadSceneJob, before you can write to the Unity.Entities.EntityManager safely.
Unity.Collections.LowLevel.Unsafe.AtomicSafetyHandle.CheckWriteAndThrowNoEarlyOut (Unity.Collections.LowLevel.Unsafe.AtomicSafetyHandle handle) <0x3a612bea8 + 0x0003f> in <eaf6a7c0e75f455b85fa84206f8b735b>:0
Unity.Collections.LowLevel.Unsafe.AtomicSafetyHandle.CheckWriteAndThrow (Unity.Collections.LowLevel.Unsafe.AtomicSafetyHandle handle) (at /Users/bokken/build/output/unity/unity/Runtime/Export/Jobs/AtomicSafetyHandle.bindings.cs:199)

ArgumentException: DeserializeWorld can only be used on completely empty World. Please create a new empty World and add Systems after loading is complete instead.
Unity.Entities.Serialization.SerializeUtility.EndDeserializeWorld (Unity.Entities.ExclusiveEntityTransaction manager, Unity.Entities.Serialization.DotsSerializationReader dotsReader, Unity.Entities.Serialization.SerializeUtility+WorldDeserializationStatus& status, Unity.Entities.Serialization.SerializeUtility+WorldDeserializationResult& deserializationResult, System.Int32 externalEntitiesRefRange, System.Int32 sceneSectionIndex, Unity.Collections.NativeArray`1[T] unityObjects) (at ./Library/PackageCache/com.unity.entities@7c40ffdd1a69/Unity.Entities/Serialization/SerializeUtility.cs:1046)
Unity.Scenes.AsyncLoadSceneOperation+AsyncLoadSceneJob.Execute () (at ./Library/PackageCache/com.unity.entities@7c40ffdd1a69/Unity.Scenes/AsyncLoadSceneOperation.cs:148)

InvalidOperationException: EntityManager cannot be used from this context because it is not part of the exclusive transaction that is currently active.
Unity.Entities.EntityManager.AssertIsExclusiveTransaction () (at ./Library/PackageCache/com.unity.entities@7c40ffdd1a69/Unity.Entities/EntityManager.cs:80)
Unity.Entities.EntityManager.GetCheckedEntityDataAccess () (at ./Library/PackageCache/com.unity.entities@7c40ffdd1a69/Unity.Entities/EntityManager.cs:90)
Unity.Entities.EntityManager.get_UniversalQueryWithSystems () (at ./Library/PackageCache/com.unity.entities@7c40ffdd1a69/Unity.Entities/EntityManager.cs:251)
Unity.Entities.Editor.UpdateHierarchySystem.OnUpdate () (at ./Library/PackageCache/com.unity.entities@7c40ffdd1a69/Unity.Entities.Editor/Hierarchy/UpdateHierarchySystem.cs:225)