Screw it, I added light

Assets/Scripts/Game/PathShadow.cs

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+using System.Collections.Generic;
+using System.Reflection;
+using UnityEngine;
+using UnityEngine.Rendering.Universal;
+
+namespace TilemapShadowCaster.Runtime
+{
+    public class PathShadow : ShadowCaster2D
+    {
+        static FieldInfo shapeFieldInfo = typeof(ShadowCaster2D).GetField("m_ShapePath",
+            BindingFlags.NonPublic | BindingFlags.Instance);
+
+        static FieldInfo shapeHashFieldInfo = typeof(ShadowCaster2D).GetField("m_ShapePathHash",
+            BindingFlags.NonPublic | BindingFlags.Instance);
+
+        static FieldInfo sortingLayersFieldInfo = typeof(ShadowCaster2D).GetField("m_ApplyToSortingLayers",
+            BindingFlags.NonPublic | BindingFlags.Instance);
+
+        internal void SetShape(List<Vector2> points,  int[] sortingLayers)
+        {
+            Vector3[] shapev3 = points.ConvertAll((point) => new Vector3(point.x, point.y)).ToArray();
+            shapeFieldInfo.SetValue(this, shapev3);
+            sortingLayersFieldInfo.SetValue(this, sortingLayers);
+            shapeHashFieldInfo.SetValue(this, (int) UnityEngine.Random.Range(0f, 10000000f));
+        }
+    }
+}

Assets/Scripts/Game/PathShadow.cs.meta

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+fileFormatVersion: 2
+guid: 2c916149db92e4f9ea5091a170cf88f2

Assets/Scripts/Game/TilemapShadowCaster2D.cs

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+using System.Collections.Generic;
+using UnityEngine;
+using System.Linq;
+
+namespace TilemapShadowCaster.Runtime
+{
+    [ExecuteInEditMode]
+    [DisallowMultipleComponent]
+    [AddComponentMenu("Rendering/2D/Tilemap Shadow Caster")]
+    public class TilemapShadowCaster2D : MonoBehaviour
+    {
+        [SerializeField] private uint colliderHash;
+        [SerializeField] private bool m_SelfShadows = false;
+        [SerializeField] private int m_ApplyToSortingLayers = -1;
+            
+        private void Update()
+        {
+            CompositeCollider2D collider = GetComponent<CompositeCollider2D>();
+            uint shapeHash = collider.GetShapeHash();
+            if (shapeHash == colliderHash) return;
+            colliderHash = shapeHash;
+            ReinitializeShapes(collider);
+        }
+
+        private int[] getLayers(){
+            int[] values = SortingLayer.layers.Select(l => l.id).ToArray();
+            List<int> sortingLayers = new List<int>();
+            int propCount = 0;
+            for (int i = 0; i < values.Length; i++)
+            {
+                int layer = 1 << i;
+                if ((m_ApplyToSortingLayers & layer) != 0)
+                {
+                    sortingLayers.Add(values[propCount]);
+                    propCount ++;
+                }
+            }
+            int[] layerArray = sortingLayers.ToArray();
+            return layerArray;
+        }
+
+        private void ReinitializeShapes(CompositeCollider2D collider)
+        {
+            RemoveCurrentShadows();
+
+            for (int i = 0; i < collider.pathCount; i++)
+            {
+                List<Vector2> points = new List<Vector2>();
+                collider.GetPath(i, points);
+
+                GameObject go = new GameObject("AutogeneratedShadowPath", typeof(MeshRenderer));
+                go.transform.parent = transform;
+                PathShadow path = go.AddComponent<PathShadow>();
+                path.useRendererSilhouette = false;
+                path.selfShadows = m_SelfShadows;
+                path.SetShape(points, getLayers());
+            }
+        }
+
+        private void RemoveCurrentShadows()
+        {
+            new List<PathShadow>(GetComponentsInChildren<PathShadow>())
+                .ConvertAll(comp => comp.transform.gameObject)
+                .ForEach(gameObject =>
+                {
+                    if (Application.isEditor)
+                    {
+                        DestroyImmediate(gameObject);
+                    }
+                    else
+                    {
+                        Destroy(gameObject);
+                    }
+                });
+        }
+
+        public void ReinitializeShapes()
+        {
+            ReinitializeShapes(GetComponent<CompositeCollider2D>());
+        }
+
+        public void OnDestroy()
+        {
+            RemoveCurrentShadows();
+        }
+    }
+
+}

Assets/Scripts/Game/TilemapShadowCaster2D.cs.meta

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+fileFormatVersion: 2
+guid: b44ee1dccb1a340e299b7e9ccd5d003b