$fileoptions = array('mainfile'=>'', 'subdirs'=>1, 'maxbytes'=>-1, 'maxfiles'=>-1, 'accepted_types'=>'*', 'return_types'=> null);
        $mform->addElement('filepicker', '{{ id }}', get_string('{{ id }}', '{{ langCategory }}'), null, $fileoptions);
{% include 'form/form-common-element.twig' %}