Siropu
Well-known member
You can achieve that by removing this part of code in ControllerPublic/Account.php:
PHP:
else if ($this->_getHistoryModel()->usernameExistsInHistory($username, $userId))
{
$errors[] = new XenForo_Phrase('siropu_username_change_exists_in_history', array('username' => $username));
}