Parallax how to work?

https://siteorigin.com/thread/how-to-add-parallax-scrolling-to-a-page-builder-row/

your-parallax-class-1

.your-parallax-class-1 {
    background-attachment: fixed;
    background-position: center;
    box-shadow: inset 0 0 1em #111;
}

Need add Plugin: jQuery Parallax
https://ianlunn.co.uk/plugins/jquery-parallax/

parallax.js

/*
Plugin: jQuery Parallax
Version 1.1.3
Author: Ian Lunn
Twitter: @IanLunn
Author URL: https://www.ianlunn.co.uk/
Plugin URL: https://www.ianlunn.co.uk/plugins/jquery-parallax/

Dual licensed under the MIT and GPL licenses:
https://www.opensource.org/licenses/mit-license.php
https://www.gnu.org/licenses/gpl.html
*/

(function( $ ){
	var $window = $(window);
	var windowHeight = $window.height();

	$window.resize(function () {
		windowHeight = $window.height();
	});

	$.fn.parallax = function(xpos, speedFactor, outerHeight) {
		var $this = $(this);
		var getHeight;
		var firstTop;
		var paddingTop = 0;

		//get the starting position of each element to have parallax applied to it
		$this.each(function(){
		    firstTop = $this.offset().top;
		});

		if (outerHeight) {
			getHeight = function(jqo) {
				return jqo.outerHeight(true);
			};
		} else {
			getHeight = function(jqo) {
				return jqo.height();
			};
		}

		// setup defaults if arguments aren't specified
		if (arguments.length < 1 || xpos === null) xpos = "50%";
		if (arguments.length < 2 || speedFactor === null) speedFactor = 0.1;
		if (arguments.length < 3 || outerHeight === null) outerHeight = true;

		// function to be called whenever the window is scrolled or resized
		function update(){
			var pos = $window.scrollTop();				

			$this.each(function(){
				var $element = $(this);
				var top = $element.offset().top;
				var height = getHeight($element);

				// Check if totally above or totally below viewport
				if (top + height < pos || top > pos + windowHeight) {
					return;
				}

				$this.css('backgroundPosition', xpos + " " + Math.round((firstTop - pos) * speedFactor) + "px");
			});
		}		

		$window.bind('scroll', update).resize(update);
		update();
	};
})(jQuery);

The second embodiment of how to implement parallax:
https://pixelcog.github.io/parallax.js/

<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.0/jquery.min.js"></script>
<script src="/path/to/parallax.js"></script>

and add class:

<div class="parallax-window" data-parallax="scroll" data-image-src="/path/to/image.jpg"></div>

https://matthew.wagerfield.com/parallax/

Hi,
In Addition to the previous Comments.
In a random page of the theme, after inserting a one column row with Page Builder and choosing:
( Edit Page) > Edit Row > (under)Row Styles > Design > Background Image Display, there is a “Parallax” Option.
Does it work or do we need an additional Parallax Plugin ?
In my case by choosing it the Image does not appear at all in my Theme.

Thank you