Edit File: StringLoader.php
<?php use Twig\Extension\StringLoaderExtension; class_exists('Twig\Extension\StringLoaderExtension'); @trigger_error(sprintf('Using the "Twig_Extension_StringLoader" class is deprecated since Twig version 2.7, use "Twig\Extension\StringLoaderExtension" instead.'), E_USER_DEPRECATED); if (\false) { /** @deprecated since Twig 2.7, use "Twig\Extension\StringLoaderExtension" instead */ class Twig_Extension_StringLoader extends StringLoaderExtension { } }