Displays posts based on what has been added to a menu location

display-content-based-on-menu.php

<?php
$menu = 'featured-content'; // Replace with your menu name
if ( has_nav_menu( $menu ) ) :
    // Get post ids of items in the menu
    $items = wp_get_nav_menu_items( $menu );
    foreach ( $items as $item ) {
        $ids[] = get_post_meta( $item->ID, '_menu_item_object_id', true );
    }

    // var_dump( $ids );
    if ( isset( $ids ) ) :
        $args = array(
            'posts_per_page' => 6, // # of posts to appear
            'post_type' => array( 'post', 'page', 'guide' ), // Post types
            'post__in' => $ids,
            'orderby' => 'post__in'
        );
        $query = new WP_Query( $args );
        if ( $query->have_posts() ) :
            while ( $query->have_posts() ) : $query->the_post(); ?>
            <div class="article">
                <a href="<?php the_permalink(); ?>">
                    <div class="image">
                        <?php the_post_thumbnail(); ?>
                    </div>
                    <h3><?php the_title(); ?></h3>
                </a>
            </div>
            <?php endwhile;
        endif;
        wp_reset_query();
    endif;
endif;