diff --git a/static/js/getTextFromFile.js b/static/js/getTextFromFile.js
index 6c6850ef..48da135c 100644
--- a/static/js/getTextFromFile.js
+++ b/static/js/getTextFromFile.js
@@ -10,7 +10,11 @@ var fileCache = function () {
 
 _cache = fileCache();
 function getTextFromFileUrl(url,header={}) {
-  return _cache[url];
+  if (url in _cache) {
+    return _cache[url];
+  } else {
+    return async () => {await getTextFromFileUrlAsync(url)};
+  }
 }