How to make that in a two-level menu, the top-level items were also links? Everything is standard:

<?php wp_nav_menu(array( 'theme_location' => 'header_menu_down', 'menu' => false , 'container' => false, 'container_class' => false , 'container_id' => false , 'menu_class' => 'nav navbar-nav', 'walker' => new wp_bootstrap_navwalker() ));?> 
  • give at least the code as you call the menu / build - Nikolay
  • Judging by the code above inside the wolf, links for compatibility with the bootstrap are removed from the first level - mihdan

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