Notes Plugin for Admin Notes on Posts & Pages

I use to need to remember problems, issues or work done in my chapters, so I decided to try to find a solution. I did found that plugin, maybe some one of you have the same problem.

(do not work with the export of pressbooks xml)
(Also you have to choose the CPT book by book and after the deleting all the content is in the database, looks like. I will ask for a solution about that)

add_filter( 'option_spnotes_settings', function( $value ) {
	$value['post_types'][] = 'your-cpt';
	return $value;
} );

You could paste the below snippet in your theme functions.php file. It should do the job.