I'm trying to retrieve messages inbox using Ajax but I'm looking at the var_dump and there's no sender GUID in the array. If I use elgg_list_entities_from_metadata, it would show show the sender as the current logged in user.

Slightly modified code from resources/messages/inbox.php:

$list = elgg_list_entities_from_metadata(array(
    'type' => 'object',
    'subtype' => 'messages',
    'metadata_name' => 'toId',
    'metadata_value' => elgg_get_logged_in_user_guid(),
    'owner_guid' => elgg_get_logged_in_user_guid(),
    'full_view' => false,
    'preload_owners' => true,
    'bulk_actions' => true
));

Here's the dump:

 [0]=>
  object(ElggObject)#363 (8) {
    ["url_override":protected]=>
    NULL
    ["temp_metadata":protected]=>
    array(0) {
    }
    ["temp_annotations":protected]=>
    array(0) {
    }
    ["temp_private_settings":protected]=>
    array(0) {
    }
    ["volatile":protected]=>
    array(0) {
    }
    ["orig_attributes":protected]=>
    array(0) {
    }
    ["attributes":protected]=>
    array(13) {
      ["guid"]=>
      int(96)
      ["type"]=>
      string(6) "object"
      ["subtype"]=>
      int(9)
      ["owner_guid"]=>
      int(42)
      ["site_guid"]=>
      int(1)
      ["container_guid"]=>
      int(42)
      ["access_id"]=>
      int(0)
      ["time_created"]=>
      int(1473995299)
      ["time_updated"]=>
      int(1473995299)
      ["last_action"]=>
      int(1473995299)
      ["enabled"]=>
      string(3) "yes"
      ["title"]=>
      string(103) "Lorem ipsum dolor sit amet, consectetur adipiscing elit. Phasellus lobortis non neque fermentum cursus."
      ["description"]=>
      string(793) "
Lorem ipsum dolor sit amet, consectetur adipiscing elit. Phasellus lobortis non neque fermentum cursus. Mauris luctus augue elementum sem condimentum venenatis. Ut tincidunt vehicula justo, non imperdiet ex dignissim non. Vestibulum et gravida eros, vitae commodo leo. Duis mauris dui, accumsan ut dolor in, accumsan vestibulum turpis. Mauris eget sem imperdiet, dictum neque in, vulputate nibh. Cras ultrices eros ac enim vehicula viverra. Sed interdum non erat a elementum. Nullam auctor malesuada lorem, id fermentum tellus congue eu. Class aptent taciti sociosqu ad litora torquent per conubia nostra, per inceptos himenaeos. Praesent auctor justo sit amet pretium ultrices. Pellentesque sit amet nisi in tellus rhoncus fermentum. Duis mattis nec metus vitae efficitur.

"
    }
    ["valid":protected]=>
    bool(false)
  }