js issue

Problem/Motivation

Install galleryslider

Steps to reproduce

in node edit or node create
we get js error

VM2396:1 Uncaught SyntaxError: "undefined" is not valid JSON
    at JSON.parse (<anonymous>)
    at first.js?rhbgku:5:16
    at dispatch (galleryslider.js?rhbgku:5378:16)
    at elemData.handle (galleryslider.js?rhbgku:5031:35)

i find file first.js is not good catch error
it must be

$(window).load(function () {
  'use strict';
  let a = $('.slider').attr('data-settings');
  if(a){
    let b = JSON.parse(a);
    if(b){
      $('.slider').gridSlide(b);
    }
  }
});