In your child-theme‘s functions.php, add the following code:
add_action('admin_bar_menu', 'add_toolbar_items', 100); function add_toolbar_items($admin_bar){ $admin_bar->add_menu( array( 'id' => 'my-item', 'title' => 'My Item', 'href' => '#', 'meta' => array( 'title' => __('My Item'), ), )); $admin_bar->add_menu( array( 'id' => 'my-sub-item', 'parent' => 'my-item', 'title' => 'My Sub Menu Item', 'href' => '#', 'meta' => array( 'title' => __('My Sub Menu Item'), 'target' => '_blank', 'class' => 'my_menu_item_class' ), )); $admin_bar->add_menu( array( 'id' => 'my-second-sub-item', 'parent' => 'my-item', 'title' => 'My Second Sub Menu Item', 'href' => '#', 'meta' => array( 'title' => __('My Second Sub Menu Item'), 'target' => '_blank', 'class' => 'my_menu_item_class' ), )); }
Change the information as needed.