Overwrite field-names with a template

In Pimcore I’m using https://github.com/dachcom-digital/pimcore-formbuilder to create input forms in my project.
I have the problem that the default input names are not the once I need for my task.

Default names
<input .. name="formbuilder_1[task]"
<input .. name="task"

I created a form theme to overwrite it

{# /templates/bundles/FormBuilderBundle/Form/Theme/myform_div_layout.html.twig #}
{% extends "form_div_layout.html.twig" %}

{%- block widget_attributes -%}
    id="{{ id }}" name="{{ name }}"
    {%- if disabled %} disabled="disabled"{% endif -%}
    {%- if required %} required="required"{% endif -%}
    {{ block('attributes') }}
{%- endblock widget_attributes -%}

The default name is {{full_name}}, replaced with {{name}} returns the fieldname I’ve set in the formbuilder form.