functions.php

<?php
add_action( 'admin_enqueue_scripts', 'ywpi_pdf_template_licence_key', 99 );
if ( ! function_exists( 'ywpi_pdf_template_licence_key' ) ) {

	function ywpi_pdf_template_licence_key() {
		$js = "wp.hooks.addFilter('ywpi_pdf_template_demo', 'yith-woocommerce-pdf-invoice/customization', (key) => {
      return 'ywpi_live_demo';

  } );";
		wp_add_inline_script( 'ywpi-pdf-template-builder-script', $js, 'after' );
	}
}
add_action( 'admin_enqueue_scripts', 'ywraq_pdf_template_licence_key', 99 );
if ( ! function_exists( 'ywraq_pdf_template_licence_key' ) ) {

	function ywraq_pdf_template_licence_key() {
		$js = "wp.hooks.addFilter('ywraq_pdf_template_demo', 'yith-woocommerce-request-a-quote/customization', (key) => {
      return 'ywraq_live_demo';

  } );";
		wp_add_inline_script( 'ywraq-pdf-template-builder-script', $js, 'after' );
	}
}