<PackageReference Include="System.Configuration.ConfigurationManager" Version="8.0.0-rc.1.23419.4" />

ConfigurationAllowDefinition

Specifies the locations within the configuration-file hierarchy that can set or override the properties contained within a ConfigurationSection object.
namespace System.Configuration { public enum ConfigurationAllowDefinition { MachineOnly = 0, MachineToWebRoot = 100, MachineToApplication = 200, Everywhere = 300 } }