diff --git a/spine-unity/Assets/Spine/Editor/spine-unity/Editor/Utility/SpineBuildProcessor.cs b/spine-unity/Assets/Spine/Editor/spine-unity/Editor/Utility/SpineBuildProcessor.cs
index 6b994b4cd..12d836ea5 100644
--- a/spine-unity/Assets/Spine/Editor/spine-unity/Editor/Utility/SpineBuildProcessor.cs
+++ b/spine-unity/Assets/Spine/Editor/spine-unity/Editor/Utility/SpineBuildProcessor.cs
@@ -36,6 +36,10 @@
 #define HAS_ON_POSTPROCESS_PREFAB
 #endif
 
+#if UNITY_2020_3_OR_NEWER
+#define HAS_SAVE_ASSET_IF_DIRTY
+#endif
+
 using System.Collections.Generic;
 using UnityEditor;
 using UnityEditor.Build;
@@ -80,13 +84,18 @@ namespace Spine.Unity.Editor {
 					string assetPath = AssetDatabase.GUIDToAssetPath(asset);
 					GameObject prefabGameObject = AssetDatabase.LoadAssetAtPath<GameObject>(assetPath);
 					if (SpineEditorUtilities.CleanupSpinePrefabMesh(prefabGameObject)) {
+#if HAS_SAVE_ASSET_IF_DIRTY
+						AssetDatabase.SaveAssetIfDirty(prefabGameObject);
+#endif
 						prefabsToRestore.Add(assetPath);
 					}
 					EditorUtility.UnloadUnusedAssetsImmediate();
 				}
 				AssetDatabase.StopAssetEditing();
+#if !HAS_SAVE_ASSET_IF_DIRTY
 				if (prefabAssets.Length > 0)
 					AssetDatabase.SaveAssets();
+#endif
 			} finally {
 				BuildUtilities.IsInSkeletonAssetBuildPreProcessing = false;
 			}
@@ -98,9 +107,14 @@ namespace Spine.Unity.Editor {
 				foreach (string assetPath in prefabsToRestore) {
 					GameObject g = AssetDatabase.LoadAssetAtPath<GameObject>(assetPath);
 					SpineEditorUtilities.SetupSpinePrefabMesh(g, null);
+#if HAS_SAVE_ASSET_IF_DIRTY
+					AssetDatabase.SaveAssetIfDirty(g);
+#endif
 				}
+#if !HAS_SAVE_ASSET_IF_DIRTY
 				if (prefabsToRestore.Count > 0)
 					AssetDatabase.SaveAssets();
+#endif
 				prefabsToRestore.Clear();
 
 			} finally {
@@ -121,11 +135,16 @@ namespace Spine.Unity.Editor {
 						spriteAtlasTexturesToRestore[assetPath] = AssetDatabase.GetAssetPath(atlasAsset.materials[0].mainTexture);
 						atlasAsset.materials[0].mainTexture = null;
 					}
+#if HAS_SAVE_ASSET_IF_DIRTY
+					AssetDatabase.SaveAssetIfDirty(atlasAsset);
+#endif
 					EditorUtility.UnloadUnusedAssetsImmediate();
 				}
 				AssetDatabase.StopAssetEditing();
+#if !HAS_SAVE_ASSET_IF_DIRTY
 				if (spriteAtlasAssets.Length > 0)
 					AssetDatabase.SaveAssets();
+#endif
 			} finally {
 				BuildUtilities.IsInSpriteAtlasBuildPreProcessing = false;
 			}
@@ -141,9 +160,14 @@ namespace Spine.Unity.Editor {
 						Texture atlasTexture = AssetDatabase.LoadAssetAtPath<Texture>(pair.Value);
 						atlasAsset.materials[0].mainTexture = atlasTexture;
 					}
+#if HAS_SAVE_ASSET_IF_DIRTY
+					AssetDatabase.SaveAssetIfDirty(atlasAsset);
+#endif
 				}
+#if !HAS_SAVE_ASSET_IF_DIRTY
 				if (spriteAtlasTexturesToRestore.Count > 0)
 					AssetDatabase.SaveAssets();
+#endif
 				spriteAtlasTexturesToRestore.Clear();
 			} finally {
 				BuildUtilities.IsInSpriteAtlasBuildPostProcessing = false;