jQuery Window

Set the width property of the jqxWindow. Author: http://jqwidgets.com

HTML

<link rel="stylesheet" href="https://jqwidgets.com/public/jqwidgets/styles/jqx.base.css">
<script src="https://jqwidgets.com/public/jqwidgets/jqx-all.js"></script>
<link rel="stylesheet" href="https://jqwidgets.com/public/jqwidgets/styles/jqx.energyblue.css">
<div id='jqxwindow'>
    <div>Header</div>
    <div>
      <div id="go-beyond">
        Go beyond div
      </div>
    </div>
</div>

CSS

#go-beyond {
  position: fixed;
}

JavaScript

$("#jqxwindow").jqxWindow({
    width: 300,
    height: 100
});

setTimeout(() => {
	const left = $('#jqxwindow').css('left')
  $("#go-beyond").css('left', left.split('px')[0]  - 40)
})


$('#jqxwindow').on('moving', function (event) { 
	/* console.log(event) */
  $("#go-beyond").css('left', event.args.x - 40)
});