title: PHP Fatal error: Class 'Twig\\Extension\\AbstractExtension' not found
body: <p>I've tried updating Symfony to v2.8.* today.</p>
  
  <p>I have this error:</p>
  
  <blockquote>
    <p>Fatal error:  Class 'Twig\Extension\AbstractExtension' not found</p>
  </blockquote>
  
  <p>Please help </p>
  
  <p>Here my composer json :</p>
  
  <pre><code>"name": "assane/myecomapp",
  "license": "proprietary",
  "type": "project",
  "autoload": {
      "psr-4": {
          "": "src/"
      },
      "classmap": [
          "app/AppKernel.php",
          "app/AppCache.php"
      ]
  },
  "require": {
      "php": "&gt;=5.3.9",
      "symfony/symfony": "2.8.*",
      "doctrine/orm": "^2.4.8",
      "doctrine/doctrine-bundle": "~1.4",
      "symfony/swiftmailer-bundle": "~2.3,&gt;=2.3.10",
      "symfony/monolog-bundle": "^3.0.2",
      "sensio/distribution-bundle": "~5.0",
      "sensio/framework-extra-bundle": "^3.0.2",
      "incenteev/composer-parameter-handler": "~2.0",
      "friendsofsymfony/user-bundle": "~2.0@dev",
      "twig/extensions":"*"
  },
  "require-dev": {
      "sensio/generator-bundle": "~3.0",
      "symfony/phpunit-bridge": "~2.7",
      "doctrine/doctrine-fixtures-bundle": "^2.3"
  },
  </code></pre>
  
  <p>Thanks</p>