Code-Snippets-Functions/Execute a function on a child site/WooCommerce/define-item-thumbnail-background-color-as-white-in-email-notifications.txt

add_filter( 'woocommerce_email_styles', 'custom_wc_email_styles', 20 );
function custom_wc_email_styles( $css ) {
    $css .= '.order_item > td > img { background-color: #ffffff; }';
    return $css;
}