How to upgrade fullcalendar version 4.4 in angular js

问题

Actually, I want upgrade fullcalendar version 4.4 in my angularjs web application. already have fullcalendar version 2.9 it very slow in my project that's i want to upgrade fullcalendar version 4.4 so please help how to upgrade this and i have tried but i'm not able to get please check my code below.

@ Note : All the js and css code i have included footer.php & header.php

Html code:

<div id='calendar44'></div>

ctrl.ordercal.js : this js all the code blow init function.

document.addEventListener('DOMContentLoaded', function() {
    var calendarEl = angular.element(document.querySelector('#calendar44'));
     lg(calendarEl);    
     alert(calendarEl);
     var calendarout = new FullCalendar.Calendar(calendarEl, { plugins: [ 'dayGrid' ]});
     alert(calendarout);    
        calendarout.render();       
});

来源：https://stackoverflow.com/questions/61811320/how-to-upgrade-fullcalendar-version-4-4-in-angular-js