Ancor is added after # to the main page (site.com/#ancor) – the site domain. But it needs to be added to the current page (site.com/category/article#ancor)
Apparently there is an error here
generateNavEl: function(anchor, text) {
var $a = $('<a class="nav-link"></a>');
$a.attr("href", "#" + anchor);
$a.text(text);
var $li = $("<li></li>");
$li.append($a);
return $li;
},
Код взят отсюда