Fixes to code in preparePost function

Right now the code is returning empty author names when creating the index (at least with my config). I suggest to replace this code (line 303):

$user = get_userdata( $post->post_author );

		if ( $user instanceof WP_User ) {
			$user_data = $user->display_name;
		} else {
			$user_data = '';
		}

with only this:

$user_data = get_the_author_meta('display_name', $post->post_author);

This way is simpler, fastest, and it works fine for me. ??