fix tag count missing

_includes/_macro/sidebar.html

@@ -64,7 +64,7 @@
             </div>
           {% endif %}
 
-          {% if site.tags.length > 0 %}
+          {% if site.tags.size > 0 %}
             {% assign tagsPageQuery = site.pages | where_exp: 'page', 'page.type == "tags"' %}
             {% if tagsPageQuery.size > 0 %}
               {% assign hasTagsPage = true %}