Modify the "return to website" text on the PayPal confirmation page, when customer is sent from Easy Digital Downloads. The default text is your site title

gistfile1.php

<?php

function my_child_theme_edd_paypal_redirect_args( $paypal_args ) {
	$paypal_args['cbt'] = 'Return to our site to complete your purchase';

	return $paypal_args;
}
add_filter( 'edd_paypal_redirect_args', 'my_child_theme_edd_paypal_redirect_args' );