I have taken on a site that has hard coded page urls in it's page.html.twig for loading specific sidebar blocks based on the url for related content. eg:
{% if 'frozen' in url|render|render %}
{# shows these blocks and in this order #}
<aside id="sidebar">
{{ block_chooserecipes }}
{{ block_healthbenefits }}
</aside>
Is there a way to create a content type field that will load the sidebar blocks that the editor wishes to include with their main content?