outline border not working in laravel excel

问题

In laravel excel I used outline border for table but it not work proper for merged cell.Outline border missing where cell merged in table.

$cellStyle = array(
  'borders' => array(
    'outline' => array(
      'style' => PHPExcel_Style_Border::BORDER_THICK
    )
  )
);

来源：https://stackoverflow.com/questions/60983946/outline-border-not-working-in-laravel-excel