Java Edition:Noname Creator
The creator field was added to save files in Classic 0.0.13a-dev. This field is initialized with the worlds creation and usually is initialized with the username of the player who created the world, but if the world is created in this version the field will be initialized with a discontinued value. This value is unobservable without the use of external tools, and is a file discontinued feature.
Obtaining
The "creator" field is usually initialized with the username of the player who created the world, but if the world is created in Classic 0.0.13a-dev this field will be initialized as "noname" instead. This is not a discontinued feature for the player named "noname". [1]
How to Observe
Because this feature is a file discontinued feature, it is unobservable in-game. The only way to view this discontinued feature is by using external tools, the ClassicExplorer tool can be used to view Classic fields.