Objects created in EditorWindow do not persist after reloading project

Hello, I've looked through a few similar questions and didn't find quite what I was looking for. There were a few questions whose solutions involved serializable fields and scriptable objects, but this felt a bit different.

Suppose I have a simple editor window that creates an object. The object will appear in the scene hierarchy correctly, but will not persist through closing / reloading the project scene.

If I manually change the object (rename, change parent, etc) using the Scene Editor itself, then the object will persist. I'm assuming there is a trivial solution for this, but have not had much time to investigate.

Thanks:

 using UnityEngine;
 using UnityEditor;
 using System.Collections;
 using System.Collections.Generic;
 
 public class CreateObjectWindow : EditorWindow
 {
     // Keep track of what we've made
     private static List<GameObject> createdObjects;
 
     [MenuItem ("Window/CreateObject")]
     public static void OpenCreateObjectWindow ()
     {
         // Make the window
         var window = EditorWindow.GetWindow (typeof(CreateObjectWindow));
 
         // Initialize the list
         createdObjects = new List<GameObject> ();
     }
 
     void OnGUI ()
     {
         // Simple single button
         if ( GUILayout.Button ("Create Object!") )
         {
             // Make some empty object
             GameObject go = new GameObject ("made in editor!");
             createdObjects.Add (go);
 
             // Check if this is persistent (which it will not be)
             bool persists = EditorUtility.IsPersistent (go);
             Debug.LogFormat ("New object will persist? {0}", persists);
         }
     }
 }