diff --git a/web_src/js/utils.js b/web_src/js/utils.js
index dc8d926f4..63896774f 100644
--- a/web_src/js/utils.js
+++ b/web_src/js/utils.js
@@ -128,12 +128,14 @@ export const uniqueArray = (array1, array2) => {
 
 export const isBase64 = (str) => {
   if(!str) return false;
-  if (str === '' || str.trim() === '' || str.length % 4 === 0) {
-    return false;
-  }
-  try {
-    return window.btoa(window.atob(str)) == str;
-  } catch (err) {
-    return false;
+  if (/^([0-9a-zA-Z+/]{4})*(([0-9a-zA-Z+/]{2}==)|([0-9a-zA-Z+/]{3}=))?$/.test(str)) {
+    try {
+      return window.btoa(window.atob(str)) == str;
+    } catch (err) {
+      return false;
+    }
+  }else{
+    return false
   }
+  
 }