static void OnPostprocessAllAssets(string[] importedAssets, string[] deletedAssets, string[] movedAssets, string[] movedFromAssetPaths)
        {
            var upgradeLog   = "UniversalRP Material log:";
            var upgradeCount = 0;

            foreach (var asset in importedAssets)
            {
                if (!asset.ToLowerInvariant().EndsWith(".mat"))
                {
                    continue;
                }

                var material = (Material)AssetDatabase.LoadAssetAtPath(asset, typeof(Material));
                if (!ShaderUtils.IsLWShader(material.shader))
                {
                    continue;
                }

                ShaderPathID id            = ShaderUtils.GetEnumFromPath(material.shader.name);
                var          wasUpgraded   = false;
                var          assetVersions = AssetDatabase.LoadAllAssetsAtPath(asset);
                AssetVersion assetVersion  = null;
                foreach (var subAsset in assetVersions)
                {
                    if (subAsset.GetType() == typeof(AssetVersion))
                    {
                        assetVersion = subAsset as AssetVersion;
                    }
                }
                var debug = "\n" + material.name;

                if (!assetVersion)
                {
                    wasUpgraded  = true;
                    assetVersion = ScriptableObject.CreateInstance <AssetVersion>();
                    if (s_CreatedAssets.Contains(asset))
                    {
                        assetVersion.version = k_Upgraders.Length;
                        s_CreatedAssets.Remove(asset);
                        InitializeLatest(material, id);
                    }
                    else
                    {
                        assetVersion.version = 0;
                    }

                    assetVersion.hideFlags = HideFlags.HideInHierarchy | HideFlags.HideInInspector | HideFlags.NotEditable;
                    AssetDatabase.AddObjectToAsset(assetVersion, asset);
                    debug += " initialized.";
                }

                while (assetVersion.version < k_Upgraders.Length)
                {
                    k_Upgraders[assetVersion.version](material, id);
                    debug += $" upgrading:v{assetVersion.version} to v{assetVersion.version + 1}";
                    assetVersion.version++;
                    wasUpgraded = true;
                }

                if (wasUpgraded)
                {
                    upgradeLog += debug;
                    upgradeCount++;
                    EditorUtility.SetDirty(assetVersion);
                    s_ImportedAssetThatNeedSaving.Add(asset);
                    s_NeedsSavingAssets = true;
                }
            }
        }