ProjectDDD/Packages/SLUnity/CustomSceneCamera.cs

using UnityEngine;
using UnityEngine.Rendering.Universal;

[RequireComponent(typeof(Camera))]
public class CustomSceneCamera : MonoBehaviour
{
    private void OnEnable()
    {
        // add stack to camera
        var cam = GetComponent<Camera>();
        SLGame.Camera.GetUniversalAdditionalCameraData().cameraStack.Insert(0, cam);
    }

    private void OnDisable()
    {
        // remove stack to camera
        var cam = GetComponent<Camera>();
        SLGame.Camera.GetUniversalAdditionalCameraData().cameraStack.Remove(cam);
    }
}