W3.JS HTML Includes
https://www.w3schools.com/w3js/w3js_html_include.aspWhen you include HTML snippets in a web page, you must secure that other functions that depends on the included HTML do not execute before the HTML is properly included. The easiest way to "hold back" code is to place it in a callback function. A callback function can be added as an argument to w3.includeHTML ():