$extra_field_row = $this->getSession()->getPage()->find('css', '#display-extra-field');
$disabled_region_row = $this->getSession()->getPage()->find('css', '.region-hidden-title');
$extra_field_row->find('css', '.handle')->dragTo($disabled_region_row);
$this->assertSession()->assertWaitOnAjaxRequest();
$extra_field_row = $this->getSession()->getPage()->find('css', '#display-extra-field');
$disabled_region_row = $this->getSession()->getPage()->find('css', '.region-hidden-title');
$extra_field_row->find('css', '.handle')->dragTo($disabled_region_row);
$this->assertSession()->assertWaitOnAjaxRequest();