composer require --dev symfony/maker-bundle symfony/console
Installing these prerequisites, i. e. development dependencies is compulsory to have a working HTML forms explicitness, suggested by Symfony.
Slim PHP itself doesn’t provide
php bin/console list make
Opportunity is missing, because Composer PHP doesn’t handle binary distributed files, attributed to a core framework itself; it’s non present.
Developer has to use his skills to promote raw code in order to retrieve running PHP HTML form built object.