diff --git a/src/components/widgets/widget/container.jsx b/src/components/widgets/widget/container.jsx
index 42d049486..f06ce6cf2 100644
--- a/src/components/widgets/widget/container.jsx
+++ b/src/components/widgets/widget/container.jsx
@@ -9,7 +9,10 @@ export function getAllClasses(options, additionalClassNames = '') {
   if (options?.style?.header === "boxedWidgets") {
     if (options?.style?.cardBlur !== undefined) {
       // eslint-disable-next-line no-param-reassign
-      additionalClassNames = additionalClassNames.concat(additionalClassNames, ` backdrop-blur${options.style.cardBlur.length ? '-' : ""}${options.style.cardBlur}`)
+      additionalClassNames = [
+        additionalClassNames,
+        `backdrop-blur${options.style.cardBlur.length ? '-' : ""}${options.style.cardBlur}`
+      ].join(' ')
     }
 
     return classNames(