Until today our registered users have not been able to create private / hidden notes with their account name displayed.
This has changed today as now private / hidden notes shows names of registered users by default. You can change that behaviour in "Access" tab by clicking on "Show your name" toggle to publish as anonymous user.
Change was provided due to requests from our users that wanted to create notes that won't be shown on their profile page, but will be shared among their friends and show them that they have created that publication.