#description_display does not work for cshs widget

Using hook_form_alter to set "#description_display" to "before" for a CSHS widget does not change the position of the field description; it stays at the bottom after the field.

To duplicate, set a form field to use "select," then $form['field_whatever']['widget']['#description_display'] = 'before';
The description text will now be positioned before the field. Change the form field to "Client-Side Hierarchical Select" widget, and the description goes back to the bottom.

Any chance of adding support for #description_display? Thanks.