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