How to add a custom field to WordPress menu item on specific registered menu

gistfile1.txt

/*
* WP Version: 6.7.2
*/

// Add the checkbox to the menu item custom fields only for main-menu
function wcd_add_product_categories_checkbox($item_id, $item) {
    // Get the global menu variable that holds the current menu being edited
    global $nav_menu_selected_id;
    
    // Get all menu locations
    $locations = get_nav_menu_locations();
    
    // Menu ID to check against
    $menu_id = 'main-menu'; // Replace with your menu ID if different

    // Check if current menu is assigned to menu_id location
    $is_menu_id = false;
    if (isset($locations[$menu_id]) && $locations[$menu_id] == $nav_menu_selected_id) {
        $is_menu_id = true;
    }
    
    // Only show the checkbox if it's the menu_id
    if ($is_menu_id) {
        wp_nonce_field('add_product_categories_nonce', '_add_product_categories_nonce_name');
        $checked = get_post_meta($item_id, '_add_product_categories', true);
        ?>
        <p class="field-add-product-categories description description-wide">
            <label for="edit-menu-item-add-product-categories-<?php echo $item_id; ?>">
                <input type="checkbox" id="edit-menu-item-add-product-categories-<?php echo $item_id; ?>" name="menu-item-add-product-categories[<?php echo $item_id; ?>]" <?php echo checked($checked, 'on', false); ?> />
                <?php esc_html_e('Add Product Categories as Submenu', 'your-theme'); ?>
            </label>
        </p>
        <?php
    }
}
add_action('wp_nav_menu_item_custom_fields', 'wcd_add_product_categories_checkbox', 10, 2);

// Save the checkbox data when updating the menu item
function wcd_save_product_categories_checkbox($menu_id, $menu_item_db_id) {
    if (!isset($_POST['_add_product_categories_nonce_name']) || !wp_verify_nonce($_POST['_add_product_categories_nonce_name'], 'add_product_categories_nonce')) {
        return;
    }

    // Check if the checkbox was ticked
    if (isset($_POST['menu-item-add-product-categories'][$menu_item_db_id])) {
        $checked = 'on';
    } else {
        $checked = 'off';
    }

    // Save the checkbox value in post meta for the menu item
    update_post_meta($menu_item_db_id, '_add_product_categories', $checked);
}
add_action('wp_update_nav_menu_item', 'wcd_save_product_categories_checkbox', 10, 2);