copypaste2/templates/Form/fields.html.twig

{% block copypaste_fake_captcha_widget %}
    {% spaceless %}
        <div id="{{ form.vars.id }}"></div>
        <script type="text/javascript">
            (function () {
                div = document.getElementById('{{ form.vars.id }}');
                input = document.createElement('input');
                input.setAttribute('type', 'hidden');
                input.setAttribute('name', '{{ form.vars.full_name }}');
                input.setAttribute('value', 'dumb_text');
                div.appendChild(input);
            })();
        </script>
    {% endspaceless %}
{% endblock %}