Thanks for the excellent plugin. I just have a small problem with it. In the add_coauthors() method in the main plugin file, you "pluck" existing coauthors' user_login on line 769:
$existing_coauthors = wp_list_pluck( get_coauthors( $post_id ), 'user_login' );
and add the current user's user_login on line 776:
$coauthors = array( $current_user->user_login );
, but when comes time to build the coauthors User objects, on line 784, you use 'user_nicename':
$author = $this->get_coauthor_by( 'user_nicename', $author_name );
In almost all WordPress installs, user_nicename and user_login are identical. It just so happens that they're not in mine. Therefore coauthors are not added. Is there a particular reason why 'user_login' isn't used everywhere?
Thanks in advance!