Select_tree with attribute required true not works

When I apply the attribute required true in select_tree field_type, the post is not saved (action save is not fired when I click on button publish/update).

My code:

array(
  'id'    => 'category-and-types',
  'type' => 'taxonomy',
  'name' => esc_html__( 'Categoria, Tipo e Subtipo', 'webpesados' ),
  'placeholder'   => esc_html__( 'Selecione', 'webpesados' ),
  'taxonomy' => 'category',
  'field_type' => 'select_tree',
  'class' => 'web_select_tree',
  'columns' => 6,
  'attributes' => array(
  'required' => false,
),