Color Strings in Item name

Hi @donzzzzz,

You can not apply scripts within the PDF documents, but you can achieve the same with this code snippet, that I just wrote for you:

/**
 * PDF Invoices & Packing Slips for WooCommerce:
 * Highlight specific words in the item names
 */
add_filter( 'wpo_wcpdf_html_filters', function( $filters ) {
	$filters[] = array( 'woocommerce_order_item_name', 'wpo_wcpdf_hihglight_item_name', 999, 3 );
	return $filters;
} );
function wpo_wcpdf_hihglight_item_name( $item_name, $item, $is_visible ) {
    $item_names_to_highlight = array(
        /* Set the word(s) to search and the color to apply, one per line */
        '(Gluten)' => 'red',
        '(Free)' => 'green',
        '(string3)' => 'blue',
    );
    foreach ( $item_names_to_highlight as $target => $color) {
        if ( strpos( $item_name, $target ) !== false ) {
            $item_name = str_replace( $target,  "<span style=\"color: {$color};\">{$target}</span>", $item_name );
        }
    }
	return $item_name;
}

If you haven’t worked with code snippets (actions/filters) or functions.php before, read this guide: How to use filters