When creating an email via the API, how do I mark it as "Preview: public"?

I’m able to create an email via the rest API just fine and can mark it as “enabled”, but can’t figure out how to mark it as “Preview: Public”. Is there a JSON field I can set while creating the email?
When I do a get on an existing email that is public, I don’t see any relevant field to indicate the preview state.
Is there maybe a different API that handles the preview state?

Doing a little more digging, I see this field in app/bundles/EmailBundle/Entity/Email.php
private $publicPreview = 0;
but setting this to True in my JSON (“publicPreview”: True,) does not result in setting the value in Mautic. I’m just not familiar enough with how the API JSON is processed into an Email PHP object.
Any pointers?