i guess you can group your blog post by publish date post. {% for group in contents|groupby('blog_post_author') %} // change this to publish_date filtered by month <li>{{ group.grouper }} <ul> {% for content in group.list %} <li>{{ content.name }}</li> {% endfor %}</ul> </li> {% endfor %}
you can try to group it by widget data, second solution is to use a JS library like this to pull all months on that field then filtered it similar to this, https://community.hubspot.com/t5/Content-Design-Questions/Blog-filters/td-p/3609 althought that is a different example but you can have the idea of using class/data attr.