wp-admin/includes/class-wp-site-health.php:2032Tests if loopbacks work as expected.
array public function get_test_loopback_requests() { $result = array( 'label' => __( 'Your site can perform loopback requests' ), 'status' => 'good', 'badge' => array( 'label' => __( 'Performance' ), 'color' => 'blue', ), 'description' => sprintf( '<p>%s</p>', __( 'Loopback requests are used to run scheduled events, and are also used by the built-in editors for themes and plugins to verify code stability.' ) ), 'actions' => '', 'test' => 'loopback_requests', ); $check_loopback = $this->can_perform_loopback(); $result['status'] = $check_loopback->status; if ( 'good' !== $result['status'] ) { $result['label'] = __( 'Your site could not complete a loopback request' ); $result['description'] .= sprintf( '<p>%s</p>', $check_loopback->message ); } return $result; }Introduced in 5.2.0. Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
src/wp-admin/includes/class-wp-site-health.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.