Fatal error: Uncaught Error: Interface "Zend\Stdlib\JsonSerializable" not found in /var/www/html/scout/app/code/Xtento/PdfCustomizer/Ui/Component/Sales/Order/Masspdf/Pdftemplates.php:20 Stack trace: #0 /var/www/html/scout/vendor/composer/ClassLoader.php(576): include() #1 /var/www/html/scout/vendor/composer/ClassLoader.php(427): Composer\Autoload\{closure}() #2 [internal function]: Composer\Autoload\ClassLoader->loadClass() #3 /var/www/html/scout/vendor/magento/framework/ObjectManager/Relations/Runtime.php(38): class_exists() #4 /var/www/html/scout/vendor/magento/framework/Interception/Config/Config.php(157): Magento\Framework\ObjectManager\Relations\Runtime->has() #5 /var/www/html/scout/vendor/magento/framework/Interception/Config/Config.php(180): Magento\Framework\Interception\Config\Config->_inheritInterception() #6 /var/www/html/scout/vendor/magento/framework/Interception/Config/Config.php(213): Magento\Framework\Interception\Config\Config->hasPlugins() #7 /var/www/html/scout/vendor/magento/framework/Interception/Config/Config.php(190): Magento\Framework\Interception\Config\Config->generateIntercepted() #8 /var/www/html/scout/vendor/magento/framework/Interception/Config/Config.php(122): Magento\Framework\Interception\Config\Config->initializeUncompiled() #9 /var/www/html/scout/vendor/magento/framework/ObjectManager/Factory/AbstractFactory.php(121): Magento\Framework\Interception\Config\Config->__construct() #10 /var/www/html/scout/vendor/magento/framework/ObjectManager/Factory/Dynamic/Developer.php(66): Magento\Framework\ObjectManager\Factory\AbstractFactory->createObject() #11 /var/www/html/scout/vendor/magento/framework/ObjectManager/ObjectManager.php(70): Magento\Framework\ObjectManager\Factory\Dynamic\Developer->create() #12 /var/www/html/scout/vendor/magento/framework/App/ObjectManager/Environment/Developer.php(84): Magento\Framework\ObjectManager\ObjectManager->get() #13 /var/www/html/scout/vendor/magento/framework/App/ObjectManagerFactory.php(191): Magento\Framework\App\ObjectManager\Environment\Developer->configureObjectManager() #14 /var/www/html/scout/vendor/magento/framework/App/Bootstrap.php(212): Magento\Framework\App\ObjectManagerFactory->create() #15 /var/www/html/scout/vendor/magento/framework/App/Bootstrap.php(127): Magento\Framework\App\Bootstrap->__construct() #16 /var/www/html/scout/pub/index.php(34): Magento\Framework\App\Bootstrap::create() #17 {main} thrown in /var/www/html/scout/app/code/Xtento/PdfCustomizer/Ui/Component/Sales/Order/Masspdf/Pdftemplates.php on line 20