Custom Editor Toolbar to make SceneView follow game play camera (Current "main camera")

SceneViewFollowGamePlayCameraEditorTools.cs

using UnityEngine;
using UnityEditor;
using UnityEditor.Overlays;
using UnityEditor.Toolbars;

#if !UNITY_EDITOR
#error This script must be placed under "Editor/" directory.
#endif

[Overlay(typeof(SceneView), "CustomToolbar/SceneViewFollowGamePlayCameraOverlay")]
public class SceneViewFollowGamePlayCameraOverlay : ToolbarOverlay
{
    SceneViewFollowGamePlayCameraOverlay() : base(
        SceneViewFollowGamePlayCameraToolbarToggle.ID
        )
    {}
}

[EditorToolbarElement(ID, typeof(SceneView))]
public class SceneViewFollowGamePlayCameraToolbarToggle : EditorToolbarToggle, IAccessContainerWindow
{
    public const string ID = "CustomToolbar/SceneViewFollowGamePlayCameraToolbarToggle";
    public static readonly string KEY_TOGGLE_STATUS = $"{ID}_ToggleStatus";

    public EditorWindow containerWindow { get; set; }
    private Camera gameplayCamera;

    public SceneViewFollowGamePlayCameraToolbarToggle()
    {
        icon = EditorGUIUtility.FindTexture("d_UnityEditor.GameView");
        tooltip = "Follow Game Play Camera";
        value = EditorPrefs.GetBool(KEY_TOGGLE_STATUS, false);
        SceneView.duringSceneGui += OnSceneGUI;
    }

    private void OnSceneGUI(SceneView view)
    {
        if (EditorApplication.isPlaying)
        {
            FollowGamePlayCamera(view);
        }
    }

    protected override void ToggleValue()
    {
        base.ToggleValue();
        EditorPrefs.SetBool(KEY_TOGGLE_STATUS, value);
    }

    private void FollowGamePlayCamera(SceneView view)
    {
        bool isValid = (view == containerWindow) && value;

        if (!isValid)
        {
            return;
        }

        if (gameplayCamera == null)
        {
            gameplayCamera = Camera.main;
        }

        if (gameplayCamera)
        {
            var target = gameplayCamera.transform;
            view.AlignViewToObject(target);
        }
    }
}