diff --git a/src/pages/Editor.tsx b/src/pages/Editor.tsx
index daa29d2..7c4fbbc 100644
--- a/src/pages/Editor.tsx
+++ b/src/pages/Editor.tsx
@@ -1012,7 +1012,7 @@ export default function Editor() {
       
       const manager = new THREE.LoadingManager();
       let object: THREE.Object3D | null = null;
-      const extension = modelInfo.extension;
+      const extension = modelInfo.extension || 'glb';
 
       if (extension === 'glb' || extension === 'gltf') {
         const loader = new GLTFLoader(manager);
@@ -5299,3 +5299,4 @@ export default function Editor() {
     </div>
   );
 }
+