Remove thumbnail column from MNM product options

wc-mnm-remove-thumbnail.php

<?php 
/**
 * Remove thumbnail column from MNM product options
 * The table column header must be removed by overriding the single-product/mnm/tablular/mnm-items-wrapper-open.php template
 */
function kia_remove_thumbnail_column() {
    remove_action( 'woocommerce_mnm_child_item_details', 'wc_mnm_template_child_item_thumbnail_open', 10 );
    remove_action( 'woocommerce_mnm_child_item_details', 'wc_mnm_template_child_item_thumbnail', 20 );
    remove_action( 'woocommerce_mnm_child_item_details', 'wc_mnm_template_child_item_section_close', 30 );
    add_filter( 'woocommerce_mnm_tabular_column_headers', 'kia_remove_thumbnail_column_header' );
}
add_action( 'woocommerce_before_mnm_items', 'kia_remove_thumbnail_column', -10 );


/**
 * Remove thumbnail column from MNM table header
 * @param array
 * @return array
 */
function kia_remove_thumbnail_column_header( $headers ) {
    if( isset( $headers['thumbnail'] ) ) {
        unset( $headers['thumbnail'] );
    }
    return $headers;
}