Uncaught TypeError when creating new post

On my site, when I go to create a new wordpress post I got this error

An error of type E_ERROR was caused in line 762 of the file /home/customer/www/DOMAIN.org/public_html/wp-content/plugins/woocommerce-pdf-invoices-packing-slips/includes/Frontend.php. Error message: Uncaught TypeError: WPO\IPS\Frontend::edi_peppol_display_classic_checkout_fields(): Argument #1 ($fields) must be of type array, bool given,

In order to be able to get the site working again, I have had to amend this line as below. is that a safe change?

Many thanks

Pat

public function edi_peppol_display_classic_checkout_fields( $fields ) {
    if ( ! is_array( $fields ) ) {
        return $fields;
    }