Disable WooCommerce 3.+ lightbox

disbale-woocommerce-3-lightbox.php

<?php // Do not include this if already open! Code goes in theme functions.php.

add_action( 'after_setup_theme', 'remove_wc_gallery_lightbox', 100 );

function remove_wc_gallery_lightbox() { 
  remove_theme_support( 'wc-product-gallery-lightbox' );
}

Add only:

add_action( 'after_setup_theme', 'remove_wc_gallery_lightbox', 100 );
function remove_wc_gallery_lightbox() {
remove_theme_support( 'wc-product-gallery-lightbox' );
}