diff --git a/src/lib/components/Keyboard.ts b/src/lib/components/Keyboard.ts
index 48fb5f50..889eb3aa 100644
--- a/src/lib/components/Keyboard.ts
+++ b/src/lib/components/Keyboard.ts
@@ -1687,7 +1687,7 @@ class SimpleKeyboard {
    */
   getKeyboardClassString = (...baseDOMClasses: any[]) => {
     const keyboardClasses = [this.keyboardDOMClass, ...baseDOMClasses].filter(
-      DOMClass => !!DOMClass
+      (DOMClass) => !!DOMClass
     );
 
     return keyboardClasses.join(" ");