CMSB 3.81 menu groups BUG?

I was recreating my menugroups as some had very old extraneous fields. I notice that the new menugroup had an extra entry for menuOrder. I thought that menuOrder was no longer required. These were recreated in CMSB 3.81

<?php return [
  'menuName' => ' App Settings ',
  '_tableName' => 'app_settings_menugroup',
  '_primaryKey' => 'num',
  'menuType' => 'menugroup',
  'listPageFields' => '',
  'listPageOrder' => '',
  'listPageSearchFields' => '',
  '_filenameFields' => '',
  '_perPageDefault' => NULL,
  'alwaysExpanded' => 0,
  'menuOrder' => 1211054592,

];