public static function nav_menu_walker( $walker ) {
		global $wp_version;

		$bail_early = [
			// WP 5.4 adds support for custom fields, no need to do this hack at all.
			version_compare( $wp_version, '5.4', '>=' ),
			// not sure about this one, was part of the original solution.
			doing_filter( 'plugins_loaded' ),
			// No need if its already loaded by another plugin.
			$walker === 'Walker_Nav_Menu_Edit_Custom_Fields',
		];

		if ( in_array( true, $bail_early ) ) {
			return $walker;
		}

		// Load custom nav menu walker class for custom field compatibility.
		if ( ! class_exists( 'Walker_Nav_Menu_Edit_Custom_Fields' ) ) {
			if ( version_compare( $wp_version, '3.6', '>=' ) ) {
				require_once POPMAKE_DIR . '/includes/modules/menus/class-nav-menu-edit-custom-fields.php';
			} else {
				require_once POPMAKE_DIR . '/includes/modules/menus/class-nav-menu-edit-custom-fields-deprecated.php';
			}
		}

		return 'Walker_Nav_Menu_Edit_Custom_Fields';
	}