UVScrollEffect.cs

using UnityEditor;
using UnityEngine;
using UnityEngine.UI;

public class UVScrollEffect : BaseMeshEffect
{
    [SerializeField] private Vector2 _scroll = new Vector2(1, 1);
    [SerializeField] private bool _playEditor;
    private Vector2 _scrollDelta;

    protected override void OnEnable()
    {
        base.OnEnable();
#if UNITY_EDITOR
        EditorApplication.update -= Repaint;
        EditorApplication.update += Repaint;
#endif
    }

    protected override void OnDisable()
    {
        base.OnDisable();
#if UNITY_EDITOR
        EditorApplication.update -= Repaint;
#endif
    }

    public override void ModifyMesh(VertexHelper vh)
    {
        if (!IsActive()) return;
        if (!_playEditor || Application.isPlaying) return;

        int vertCount = vh.currentVertCount;

        _scrollDelta = _scroll * Time.time;

        UIVertex vert = new UIVertex();

        for (var i = 0; i < vertCount; i++)
        {
            vh.PopulateUIVertex(ref vert, i);
#if UNITY_2020_2_OR_NEWER
                vert.uv0 += (Vector4)_scrollDelta;
#else
            vert.uv0 += scrollDelta;
#endif
            vh.SetUIVertex(vert, i);
        }
    }

    private void Update()
    {
        graphic.SetVerticesDirty();
    }

#if UNITY_EDITOR
        private void Repaint()
        {
            if (!_playEditor || Application.isPlaying) return;
            EditorApplication.QueuePlayerLoopUpdate();
            graphic.SetVerticesDirty();
        }
#endif
}