The heartbeat_send allows you to modify the Heartbeat response sent when no $_POST data is passed. It is the logged-in, privileged sibling of heartbeat_nopriv_send.

It was added in 3.6.

It is evaluated in wp_ajax_heartbeat() in the wp-admin/includes/ajax-actions.php file.

Like heartbeat_nopriv_send, heartbeat_send accepts 2 arguments:

1. array|object $response The response object or array.
2. string $screen_id The screen id.

Example:

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