No FadeIn animation on items loaded by InfiniteScroll

Hello!
I faced a minor problem with InfiniteScroll in portfolio widget. Usually when I hover my mouse over portfolio item two buttons appears. But it doesn't work with items just loaded by InfiniteScroll. There's buttons on items but there's no animation when I hover my mouse so buttons stays invisible (opacity: 0).
Also there's this problem even on official site, here's a link: https://themes.semicolonweb.com/html/canvas/portfolio-infinity-scroll.html
My code:

		jQuery(window).on( 'load', function(){

			var $container = $('.grid-container');

			$container.infiniteScroll({
				path: '.load-next-portfolio',
				button: '.load-next-portfolio',
				scrollThreshold: false,
				history: false,
				status: '.page-load-status'
			});

			$container.on( 'load.infiniteScroll', function( event, response, path ) {
				var $items = $( response ).find('.portfolio-item');
				// append items after images loaded
				$items.imagesLoaded( function() {
					$container.append( $items );
					$container.isotope( 'insert', $items );
					setTimeout( function(){
						$container.isotope('layout');
						SEMICOLON.widget.loadFlexSlider();
						SEMICOLON.portfolio.arrange();
						SEMICOLON.initialize.lightbox();
						SEMICOLON.portfolio.portfolioDescMargin();
					}, 1000 );
				});
			});

		});

	

Works perfectly! Thank you a lot!
Add this code to the documentation as well, so no one will face this kind of problem anymore