I'm using Drupal 8 with an Adaptivetheme subtheme. The horizontal navigation menu resides in the leader board region. Some menu entries have submenus, but they do not show on the start page. One has to click on the respective menu (e.g. "Football"), which loads the single page "Football", and it is only here that submenus will be shown.
Is there a way to make submenus work on the start page with Adaptivetheme?