diff --git a/spine-flutter/lib/spine_flutter.dart b/spine-flutter/lib/spine_flutter.dart
index a5fdd51eb..af096f744 100644
--- a/spine-flutter/lib/spine_flutter.dart
+++ b/spine-flutter/lib/spine_flutter.dart
@@ -183,6 +183,11 @@ class Atlas {
     for (final image in atlasPages) {
       image.dispose();
     }
+    for (final map in atlasPagePaints) {
+      map.values.forEach((element) {
+        element.shader?.dispose();
+      });
+    }
   }
 }
 
diff --git a/spine-flutter/src/spine_flutter.cpp b/spine-flutter/src/spine_flutter.cpp
index d6441abea..a8be43800 100644
--- a/spine-flutter/src/spine_flutter.cpp
+++ b/spine-flutter/src/spine_flutter.cpp
@@ -1863,6 +1863,12 @@ spine_blend_mode spine_slot_data_get_blend_mode(spine_slot_data slot) {
 	return (spine_blend_mode) _slot->getBlendMode();
 }
 
+void spine_slot_data_set_blend_mode(spine_slot_data slot, spine_blend_mode blendMode) {
+	if (slot == nullptr) return;
+	SlotData *_slot = (SlotData *) slot;
+	_slot->setBlendMode((BlendMode) blendMode);
+}
+
 // Slot
 void spine_slot_set_to_setup_pose(spine_slot slot) {
 	if (slot == nullptr) return;
diff --git a/spine-unity/Assets/Spine/Runtime/spine-unity/Asset Types/SkeletonDataCompatibility.cs b/spine-unity/Assets/Spine/Runtime/spine-unity/Asset Types/SkeletonDataCompatibility.cs
index 421eecd31..d9e2b72eb 100644
--- a/spine-unity/Assets/Spine/Runtime/spine-unity/Asset Types/SkeletonDataCompatibility.cs	
+++ b/spine-unity/Assets/Spine/Runtime/spine-unity/Asset Types/SkeletonDataCompatibility.cs	
@@ -163,6 +163,12 @@ namespace Spine.Unity {
 
 		public static bool IsJsonFile (TextAsset file) {
 			byte[] content = file.bytes;
+
+			// check for binary skeleton version number string, starts after 8 byte hash
+			char majorVersionChar = compatibleBinaryVersions[0][0].ToString()[0];
+			if (content.Length > 10 && content[9] == majorVersionChar && content[10] == '.')
+				return false;
+
 			const int maxCharsToCheck = 256;
 			int numCharsToCheck = Math.Min(content.Length, maxCharsToCheck);
 			int i = 0;
diff --git a/spine-unity/Assets/Spine/package.json b/spine-unity/Assets/Spine/package.json
index f6200d591..23f530845 100644
--- a/spine-unity/Assets/Spine/package.json
+++ b/spine-unity/Assets/Spine/package.json
@@ -2,7 +2,7 @@
 	"name": "com.esotericsoftware.spine.spine-unity",
 	"displayName": "spine-unity Runtime",
 	"description": "This plugin provides the spine-unity runtime core.",
-	"version": "4.2.53",
+	"version": "4.2.54",
 	"unity": "2018.3",
 	"author": {
 		"name": "Esoteric Software",