The String widget displays a string as-is. If it is given a value that is not a string, it will convert it to a string representation.
Set widgetType to 'string' to use the String widget. It is also the default widget for the generic plugin, which means it will be used if you don't specify any widgetType.
{
plugin: 'generic',
widgetType: 'string',
datasourceId: 'MyDatasource',
displayName: 'Something',
fieldName: 'foo'
}
See also widgets.