View file phpBB3/vendor/twig/twig/lib/Twig/Filter.php

<?php

use Twig\TwigFilter;

class_exists('Twig\TwigFilter');

@trigger_error('Using the "Twig_Filter" class is deprecated since Twig version 2.7, use "Twig\TwigFilter" instead.', \E_USER_DEPRECATED);

if (false) {
    /** @deprecated since Twig 2.7, use "Twig\TwigFilter" instead */
    class Twig_Filter extends TwigFilter
    {
    }
}