Custom Scene View Delegate

Editor/SceneViewToolbar/SceneViewToolbar.Overlays.cs

         {
             const string prefix = "IngredientsToolbarOverlay.";
             public IngredientsToolbarOverlay() : base(
-                PlayFromHereButton.id, 
-                LinkGameViewButton.id, 
-                PointOfViewButton.id, 
-                CommentsButton.id, 
+                PlayFromHereButton.id,
+                LinkGameViewButton.id,
+                PointOfViewButton.id,
+                CommentsButton.id,
-                ) { }
+                )
+            { }
 
             protected override Layout supportedLayouts => Layout.HorizontalToolbar | Layout.VerticalToolbar;
 
                 {
                     var m = new GenericMenu();
                     m.AddItem(new GUIContent("Link Camera"), LinkGameView.LockedSceneView == containerWindow as SceneView,
-                        () => {
+                        () =>
+                        {
-                        () => {
+                        () =>
+                        {
                             LinkGameView.CinemachineActive = true;
                             value = true;
                             UpdateIcon();
             }
             #endregion
 
-
             static class Contents
             {
                 public static Texture2D playFromHere;
                     ingredientsExplorer = EditorGUIUtility.Load("Packages/net.peeweek.gameplay-ingredients/Icons/Misc/ic-callable.png") as Texture2D;
                 }
             }
+        }
+
+        [Overlay(typeof(SceneView), "Custom (Gameplay Ingredients)", true)]
+        public class IngredientsCustomToolbarOverlay : Overlay, IAccessContainerWindow
+        {
+            EditorWindow IAccessContainerWindow.containerWindow { get; set; }
+            SceneView sceneView => containerWindow as SceneView;
+
+            protected override Layout supportedLayouts => Layout.HorizontalToolbar;
+
+            public override VisualElement CreatePanelContent()
+            {
+                return new IMGUIContainer(() =>
+                {
+                    using(new GUILayout.HorizontalScope(EditorStyles.toolbar))
+                    {
+                        SceneViewToolbar.OnSceneViewToolbarGUI?.Invoke(sceneView);
+                    }
+                });
+            }
+
         }
     }
 }

Editor/SceneViewToolbar/SceneViewToolbar.cs

     {
 
 #if !UNITY_2021_2_OR_NEWER
-        public delegate void SceneViewToolbarDelegate(SceneView sceneView);
-
-        public static event SceneViewToolbarDelegate OnSceneViewToolbarGUI;
 
         [InitializeOnLoadMethod]
         static void Initialize()

Editor/SceneViewToolbar/SceneViewToolbar.Delegate.cs

+using System.Collections.Generic;
+using UnityEngine;
+using UnityEditor;
+using System;
+using GameplayIngredients.Comments.Editor;
+
+namespace GameplayIngredients.Editor
+{
+    public static partial class SceneViewToolbar
+    {
+        public delegate void SceneViewToolbarDelegate(SceneView sceneView);
+        public static event SceneViewToolbarDelegate OnSceneViewToolbarGUI;
+    }
+}

Editor/SceneViewToolbar/SceneViewToolbar.Delegate.cs.meta

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