/home/grlogisticsandse/www/wp-content/plugins/ninja-forms/includes/Templates/fields-button.html
<script id='tmpl-nf-field-button' type='text/template'>
    <button id="nf-field-{{{ data.id }}}" name="nf-field-{{{ data.id }}}" class="{{{ data.classes }}} nf-element">
        {{{ ( data.maybeFilterHTML() === 'true' ) ? _.escape( data.label ) : data.label }}}
    </button>
</script>
Path: home/grlogisticsandse/www/wp-content/plugins/ninja-forms/includes/Templates