JSFiddle - React, Tailwind, and code Playground

HTML

<script src="http://dimsemenov.com/plugins/magnific-popup/dist/jquery.magnific-popup.min.js?v=0.9.9"></script>
<button class="add-wishlist"><span>Wishlist</span></button>

JavaScript

$(document).on('click', '.add-wishlist', function(e) {
    var yes = "1";
    
    if (yes == "2"){
        // Add to wishlist
    }else {
        // Display error in popup
        displayError();
        
    }
    
});

function displayError() {
		$.magnificPopup.open({
			    items: {
			        src: '<div class="modal-content">'
			        		+'<p class="error">'
			        		+'<strong>Whoops!</strong></p>'
			        		+'<p>You cannot do that.</p></div>',
			        		
			        type:'inline',
			    },
			    closeBtnInside: true
	     });
}