Please note there is a shortcoming in how the users are displayed in the basic "user" field in MetaBox.
When the users are listed and 2 users have the same first name or display name selected, there is no way to tell them apart!
I would recommend to list all users as: [First-Name] [Last-Name] ([username])
As an alternative, you could allow to customise how the users are shown in this field through its definition. I could not find any way to do so in the docs, so if this is already feasible please let me know how 🙂
PS: my code is:
'id' => $prefix . 'submitted_by',
'type' => 'user',
'name' => esc_html__( 'Submitted By', 'timtopham' ),
'query_args' => array(
'role__in' => array('author','administrator','mentor'),
'field_type' => 'select_advanced',
'desc' => esc_html__( 'Pick a User', 'timtopham' ),