Use getBoundingClientRect instead of jQuery

js/src/modal.js

@@ -426,7 +426,8 @@ const Modal = (($) => {
     }
 
     _checkScrollbar() {
-      this._isBodyOverflowing = $('body').outerWidth(true) < window.innerWidth
+      const rect = document.body.getBoundingClientRect()
+      this._isBodyOverflowing = rect.left + rect.right < window.innerWidth
       this._scrollbarWidth = this._getScrollbarWidth()
     }