如何将属性添加到twig symfony表单中的第一个选择选项

I need to add a few attributes (f.e. disabled and selected) to the first option in select tag.

this line {{ form_widget(form.idkategoria) }} in twig render:

<select id="foo" name="foo">
<option value="">Kategoria</option>
<option value="1">foo</option>
<option value="2">foo</option>

or how to add an 'attr' to placeholder to keep default 'Kategoria' text.

$builder->add('idkategoria', null, array
                ('placeholder' => 'Kategoria',))

Something like

$builder->add('idkategoria', null, ['attr' => ['placeholder' =>'Kategoria']]) ]

You can find an extract in the official documentation