diff --git a/common/blockly-core/plugins/screenshot.js b/common/blockly-core/plugins/screenshot.js
index a20ebab3..a3a135b3 100644
--- a/common/blockly-core/plugins/screenshot.js
+++ b/common/blockly-core/plugins/screenshot.js
@@ -56,6 +56,7 @@ Blockly.Screenshot.getBase64Image_ = function(image) {
         const href = image.getAttribute('xlink:href');
         if (!href) {
             resolve();
+            return;
         }
         img.src = href;
         img.onload = function () {