setup/includes/upgrades/common/2.4-namespace-access.php
<?php
$classes = array(
'modAccessNamespace',
);
if (!empty($classes)) {
$this->createTable($classes);
}
/** @var modSystemSetting $setting */
$setting = $modx->getObject('modSystemSetting',array(
'key' => 'principal_targets',
));
if ($setting) {
$value = $setting->get('value');
$value = explode(',',$value);
$value[] = 'modAccessNamespace';
$value = array_unique($value);
$setting->set('value',implode(',',$value));
$setting->save();
}