You could also use ‘post_parent’ => 0. All unattached attachments are assigned ‘post_parent’ = 0. Here is where I found that. I’m sure that there is a more authoritative resource somewhere, but this worked for me. 🙂
You could also use ‘post_parent’ => 0. All unattached attachments are assigned ‘post_parent’ = 0. Here is where I found that. I’m sure that there is a more authoritative resource somewhere, but this worked for me. 🙂