Fatal error: Uncaught Twig\Error\SyntaxError: Unknown "get_theme_folder" function. in /var/www/html/app/Resources/TwigBundle/views/Exception/error500.html.twig:1 Stack trace: #0 /var/www/html/vendor/twig/twig/src/ExpressionParser.php(451): Twig\ExpressionParser->getFunctionNodeClass('get_theme_folde...', 1) #1 /var/www/html/vendor/twig/twig/src/ExpressionParser.php(235): Twig\ExpressionParser->getFunctionNode('get_theme_folde...', 1) #2 /var/www/html/vendor/twig/twig/src/ExpressionParser.php(175): Twig\ExpressionParser->parsePrimaryExpression() #3 /var/www/html/vendor/twig/twig/src/ExpressionParser.php(70): Twig\ExpressionParser->getPrimary() #4 /var/www/html/vendor/twig/twig/src/ExpressionParser.php(83): Twig\ExpressionParser->parseExpression(41) #5 /var/www/html/vendor/twig/twig/src/TokenParser/ExtendsTokenParser.php(39): Twig\ExpressionParser->parseExpression() #6 /var/www/html/vendor/twig/twig/src/Parser.php(185): Twig\TokenParser\ExtendsTokenParser->parse(Object(Twig\Token)) #7 /var/www/html/vendor/twig/twig/src/Pars in /var/www/html/app/Resources/TwigBundle/views/Exception/error500.html.twig on line 1