Here are a few examples of deprecated features in .NET Core:

ASP.NET Web Forms: Web Forms, a framework for building web applications, is considered deprecated in .NET Core. The recommended approach for web development in .NET Core is using ASP.NET Core MVC or Razor Pages.

WCF (Windows Communication Foundation): WCF is a framework for building distributed applications. In .NET Core, WCF is not included as a supported framework. Instead, .NET Core focuses on building lightweight and cross-platform web APIs using ASP.NET Core.

ASP.NET Web API 2: While ASP.NET Web API 2 is not officially deprecated, it is considered a legacy technology. ASP.NET Core provides a more modern and lightweight approach to building web APIs, and migrating to ASP.NET Core WebAPI is recommended for new projects.

AppDomain and related APIs: In .NET Core, the AppDomain class and related APIs are marked as deprecated. The application domains are not used in the same way as in the full .NET Framework, as .NET Core applications run in a single application domain by default.

ConfigurationManager class: The ConfigurationManager class, used for accessing configuration settings in .NET Framework applications, is not available in .NET Core. Instead, .NET Core provides a more flexible and modular configuration system based on IConfiguration.