Keys should be in lowercase and contain only alphabet, numbers and dashes '-'.

list_position(); ?>

list_groups(is_array($this->last_input['groups'])?$this->last_input['groups']:0); ?>

Select which groups are included in your box

list_post_types(is_array($this->last_input['post_types'])?$this->last_input['post_types']:0); ?>

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