Captions are not shown

Hi,

I’m using tiled gallery with magnific popup plugin. Everthing is good but I’ve a little problem:

When use any gallery which jetpack provides, captions of images disappears on magnific popup. I tried standart wordpress gallery and captions working without any problem.

My code for magnific popup is here:

/*	magnific popup */
	$('.postWrap a[href$=".jpg"], .postWrap a[href$=".jpeg"], .postWrap a[href$=".png"], .postWrap a[href$=".gif"], .postWrap a[href$=".bmp"]').magnificPopup({
		type: 'image',
		closeOnContentClick: false,
		closeBtnInside: false,
		image: {
			verticalFit: true,
			titleSrc: function(item) {
				return item.el.find('img').attr('alt');
			}
		},
		gallery: {
			enabled: true,
			tCounter: '%curr% / %total%',
		},
		callbacks: {
			open: function () {
				$('.scrolltotop').hide();
			},
			close: function () {
				$('.scrolltotop').show();
			}
		}
	});

I believe, ‘img’ and ‘alt’ parts needs change when I use Jetpack’s galleries. But how?

https://www.ads-software.com/plugins/jetpack/