<PackageReference Include="Microsoft.Extensions.DependencyInjection" Version="11.0.0-preview.2.26159.112" />

System.Diagnostics.CodeAnalysis.FeatureSwitchDefinitionAttribute

Indicates that the specified public static boolean get-only property corresponds to the feature switch specified by name.
namespace System.Diagnostics.CodeAnalysis { internal sealed class FeatureSwitchDefinitionAttribute : Attribute { public string SwitchName { get; } public FeatureSwitchDefinitionAttribute(string switchName); } }