This data-source enables you to manually configure the items of a compatible editor, e.g. Data List.
The configuration of the User-defined List data-source has the following options:
Press "Add item" button and fill the fields manually, or choose the advanced option to paste in the raw JSON.
The value for the User-defined List data-source item is a string.
Depending on the List editor used, this may be wrapped in a List<string>.