diff --git a/static/extensions/MubiLop/spritesheeter.js b/static/extensions/MubiLop/spritesheeter.js
index 2b65a2fe4..5972c28c4 100644
--- a/static/extensions/MubiLop/spritesheeter.js
+++ b/static/extensions/MubiLop/spritesheeter.js
@@ -43,7 +43,7 @@
         this.frameNames = [];
       }
       
-      loadImage(url) {
+      async loadImage(url) {
         if (await Scratch.canFetch(url) === false) return;
           
         return new Promise((resolve, reject) => {