Breaking changes in ASP.NET Core 6

If you're migrating an app to ASP.NET Core 6, the breaking changes listed here might affect you.

This article indicates whether each breaking change is binary compatible or source compatible:

• Binary compatible - Existing binaries will load and execute successfully without recompilation, and the runtime behavior won't change.
• Source compatible - Source code will compile successfully without changes when targeting the new runtime or using the new SDK or component.

Title	Binary compatible	Source compatible
ActionResult<T> sets StatusCode to 200	✔️	❌
AddDataAnnotationsValidation method made obsolete	✔️	❌
Assemblies removed from Microsoft.AspNetCore.App shared framework	❌	✔️
Blazor: Parameter name changed in RequestImageFileAsync method	✔️	❌
Blazor: WebEventDescriptor.EventArgsType property replaced	❌	❌
Blazor: Byte array interop	✔️	❌
Changed MessagePack library in @microsoft/signalr-protocol-msgpack	❌	✔️
ClientCertificate property doesn't trigger renegotiation for HttpSys	✔️	❌
EndpointName metadata not set automatically	✔️	❌
Identity: Default Bootstrap version of UI changed	❌	❌
Kestrel: Log message attributes changed	✔️	❌
Microsoft.AspNetCore.Http.Features split	❌	✔️
Middleware: HTTPS redirection middleware throws exception on ambiguous HTTPS ports	✔️	❌
Middleware: New Use overload	✔️	❌
Minimal API renames in RC 1	❌	❌
Minimal API renames in RC 2	❌	❌
MVC doesn't buffer IAsyncEnumerable types when using System.Text.Json	✔️	❌
Nullable reference type annotations changed	✔️	❌
Obsoleted and removed APIs	✔️	❌
PreserveCompilationContext not configured by default	❌	✔️
Razor: Compiler no longer produces a Views assembly	✔️	❌
Razor: Logging ID changes	❌	✔️
Razor: RazorEngine APIs marked obsolete	✔️	❌
SignalR: Java Client updated to RxJava3	❌	✔️
TryParse and BindAsync methods are validated	❌	❌