-is_deeply([$sto->maildir_keywords('/foo:2,')], [], 'Maildir no keywords');
-is_deeply([$sto->maildir_keywords('/foo:2,S')], ['seen'], 'Maildir seen');
-is_deeply([$sto->maildir_keywords('/foo:2,RS')], ['answered', 'seen'],
- 'Maildir answered + seen');
-is_deeply([$sto->maildir_keywords('/foo:2,RSZ')], ['answered', 'seen'],
- 'Maildir answered + seen w/o Z');