Custom Editor showing twice?

Hi

I've been trying to make a custom editor to show lists in a different manner in my scriptable objects. I kept having an issue where it wasn't rendering right (It would show twice in the inspector even though it should only show once.)

While trying to find a fix, I found a tutorial about the same thing I was doing, so I tried following it. What's really confusing is when I followed it I had the same issue.

This is what the issue I'm getting looks like, since it's sort of hard to explain in words:

It should only be showing The Size and list of elements once, instead it's showing them twice. I tried googling for solutions and the only one I could find suggested setting the layout to default and closing/reopening Unity. I tried this, as well as uninstalling all versions of Unity/Unity Hub and reinstalling, and tried updating versions of unity to the latest stable release.

This is the ListEditor class: using UnityEditor; using UnityEngine; using System;

 [Flags]
 public enum ListEditorOptions
 {
     None = 0,
     ListSize = 1,
     ListLabel = 2,
     ElementLabels = 4,
     Buttons = 8,
     Default = ListSize | ListLabel | ElementLabels,
     NoElementLabels = ListSize | ListLabel,
     All = Default | Buttons
 }
 
 public static class ListEditor
 {
 
     private static GUIContent
         moveButtonContent = new GUIContent("\u21b4", "move down"),
         duplicateButtonContent = new GUIContent("+", "duplicate"),
         deleteButtonContent = new GUIContent("-", "delete"),
         addButtonContent = new GUIContent("+", "add element");
 
     private static GUILayoutOption miniButtonWidth = GUILayout.Width(20f);
 
     public static void Show(SerializedProperty list, ListEditorOptions options = ListEditorOptions.Default)
     {
         if (!list.isArray)
         {
             EditorGUILayout.HelpBox(list.name + " is neither an array nor a list!", MessageType.Error);
             return;
         }
 
         bool
             showListLabel = (options & ListEditorOptions.ListLabel) != 0,
             showListSize = (options & ListEditorOptions.ListSize) != 0;
 
         if (showListLabel)
         {
             EditorGUILayout.PropertyField(list);
             EditorGUI.indentLevel += 1;
         }
         if (!showListLabel || list.isExpanded)
         {
             SerializedProperty size = list.FindPropertyRelative("Array.size");
             if (showListSize)
             {
                 EditorGUILayout.PropertyField(size);
             }
             if (size.hasMultipleDifferentValues)
             {
                 EditorGUILayout.HelpBox("Not showing lists with different sizes.", MessageType.Info);
             }
             else
             {
                 ShowElements(list, options);
             }
         }
         if (showListLabel)
         {
             EditorGUI.indentLevel -= 1;
         }
     }
 
     private static void ShowElements(SerializedProperty list, ListEditorOptions options)
     {
         bool
             showElementLabels = (options & ListEditorOptions.ElementLabels) != 0,
             showButtons = (options & ListEditorOptions.Buttons) != 0;
 
         for (int i = 0; i < list.arraySize; i++)
         {
             if (showButtons)
             {
                 EditorGUILayout.BeginHorizontal();
             }
             if (showElementLabels)
             {
                 EditorGUILayout.PropertyField(list.GetArrayElementAtIndex(i));
             }
             else
             {
                 EditorGUILayout.PropertyField(list.GetArrayElementAtIndex(i), GUIContent.none);
             }
             if (showButtons)
             {
                 ShowButtons(list, i);
                 EditorGUILayout.EndHorizontal();
             }
         }
         if (showButtons && list.arraySize == 0 && GUILayout.Button(addButtonContent, EditorStyles.miniButton))
         {
             list.arraySize += 1;
         }
     }
 
     private static void ShowButtons(SerializedProperty list, int index)
     {
         if (GUILayout.Button(moveButtonContent, EditorStyles.miniButtonLeft, miniButtonWidth))
         {
             list.MoveArrayElement(index, index + 1);
         }
         if (GUILayout.Button(duplicateButtonContent, EditorStyles.miniButtonMid, miniButtonWidth))
         {
             list.InsertArrayElementAtIndex(index);
         }
         if (GUILayout.Button(deleteButtonContent, EditorStyles.miniButtonRight, miniButtonWidth))
         {
             int oldSize = list.arraySize;
             list.DeleteArrayElementAtIndex(index);
             if (list.arraySize == oldSize)
             {
                 list.DeleteArrayElementAtIndex(index);
             }
         }
     }
 }

And this is where I'm calling it from:

         public override void OnInspectorGUI()
         {
             soTarget.Update();
             EditorGUI.BeginChangeCheck();
 
             ListEditor.Show(soTarget.FindProperty("possibleGenerators"));

             if (EditorGUI.EndChangeCheck() || GUI.changed)
             {
                 Undo.RecordObject(myTarget, "Save Cavern Parameters");
                 EditorUtility.SetDirty(myTarget);
                 soTarget.ApplyModifiedProperties();
                 AssetDatabase.SaveAssets();
             }
 
             EditorGUI.EndChangeCheck();
         }