How to render only markup in region template?
/**
 * Implements hook_preprocess_page() for page.html.twig.
 */
 function hook_preprocess_page(array &amp;$variables) {
   $variables['page']['footer'] = [     # Specify the region name
     '#theme_wrappers' =&gt; ['region'],
     '#region' =&gt; 'footer',             # Specify the region name
     'phantom_block' =&gt; [
       '#markup' =&gt; ' ',
       '#weight' =&gt; "-100",
     ],
   ];
 }


This way you are adding a block with a space to the region. Forcing Drupal to render that region. But as you will put a static HTML in that region, the content of the phantom block will not be rendered.