textareahtml.twig field validation required is not set as attrivute in html

[gitbitpi]

I have a form textfield which is set to be required, but there is no validation, when I send the form.
When i insert
{% if field.validate.required in ['on', 'true', 1] %}required="required"{% endif %}
in to the grav-theme-bootstrap4/templates/forms/fields/textarea/textfield.html.twig everything works OK.
So it looks to me like a bug