Rack Focus For The HDRP and NEW postprocessing Stack V2

using UnityEngine;
using UnityEngine.Rendering.PostProcessing;
// make sure you add this to enable the Unity Postprocessing library

public class VignettePulse : MonoBehaviour
//name the Script the Way you want
{
    PostProcessVolume m_Volume;
//A customized PostProcessVolume and its profile

    Vignette m_Vignette;
// A customized instance of the profile and its settings

    void Start()
    {
        m_Vignette = ScriptableObject.CreateInstance<Vignette>();
        m_Vignette.enabled.Override(true);
        m_Vignette.intensity.Override(1f);
//Name the setting, attach it with a temp scriptable game object

        m_Volume = PostProcessManager.instance.QuickVolume(gameObject.layer, 100f, m_Vignette);
// Assign this to the volume, make sure you got the layer correct. Currently it will read the layer of the game object it is attaching.
    }

    void Update()
    {
        m_Vignette.intensity.value = Mathf.Sin(Time.realtimeSinceStartup);
    }

    void Destroy()
    {
        RuntimeUtilities.DestroyVolume(m_Volume, true);
    }
}


https://docs.unity3d.com/Packages/com.unity.postprocessing@2.0/manual/Manipulating-the-Stack.html