diff --git a/release-notes/3.0/preview/api-diff/preview9/.Net/3.0-preview9.md b/release-notes/3.0/preview/api-diff/preview9/.Net/3.0-preview9.md
new file mode 100644
index 00000000..36fe5f24
--- /dev/null
+++ b/release-notes/3.0/preview/api-diff/preview9/.Net/3.0-preview9.md
@@ -0,0 +1,12 @@
+# API Difference netcoreapp3.0-preview8 vs netcoreapp3.0-preview9
+
+API listing follows standard diff formatting. Lines preceded by a '+' are
+additions and a '-' indicates removal.
+
+* [Microsoft.VisualBasic.ApplicationServices](3.0-preview9_Microsoft.VisualBasic.ApplicationServices.md)
+* [Microsoft.VisualBasic.Devices](3.0-preview9_Microsoft.VisualBasic.Devices.md)
+* [Microsoft.VisualBasic.MyServices](3.0-preview9_Microsoft.VisualBasic.MyServices.md)
+* [System.Net.Sockets](3.0-preview9_System.Net.Sockets.md)
+* [System.Text.Encodings.Web](3.0-preview9_System.Text.Encodings.Web.md)
+* [System.Text.Json](3.0-preview9_System.Text.Json.md)
+
diff --git a/release-notes/3.0/preview/api-diff/preview9/.Net/3.0-preview9_Microsoft.VisualBasic.ApplicationServices.md b/release-notes/3.0/preview/api-diff/preview9/.Net/3.0-preview9_Microsoft.VisualBasic.ApplicationServices.md
new file mode 100644
index 00000000..cfc24a74
--- /dev/null
+++ b/release-notes/3.0/preview/api-diff/preview9/.Net/3.0-preview9_Microsoft.VisualBasic.ApplicationServices.md
@@ -0,0 +1,101 @@
+# Microsoft.VisualBasic.ApplicationServices
+
+``` diff
+-namespace Microsoft.VisualBasic.ApplicationServices {
+ {
+-    public class ApplicationBase {
+ {
+-        public ApplicationBase();
+
+-        public CultureInfo Culture { get; }
+
+-        public AssemblyInfo Info { get; }
+
+-        public CultureInfo UICulture { get; }
+
+-        public void ChangeCulture(string cultureName);
+
+-        public void ChangeUICulture(string cultureName);
+
+-        public string GetEnvironmentVariable(string name);
+
+-    }
+-    public class AssemblyInfo {
+ {
+-        public AssemblyInfo(Assembly currentAssembly);
+
+-        public string AssemblyName { get; }
+
+-        public string CompanyName { get; }
+
+-        public string Copyright { get; }
+
+-        public string Description { get; }
+
+-        public string DirectoryPath { get; }
+
+-        public ReadOnlyCollection<Assembly> LoadedAssemblies { get; }
+
+-        public string ProductName { get; }
+
+-        public string StackTrace { get; }
+
+-        public string Title { get; }
+
+-        public string Trademark { get; }
+
+-        public Version Version { get; }
+
+-        public long WorkingSet { get; }
+
+-    }
+-    public class ConsoleApplicationBase : ApplicationBase {
+ {
+-        public ConsoleApplicationBase();
+
+-        public ReadOnlyCollection<string> CommandLineArgs { get; }
+
+-        protected ReadOnlyCollection<string> InternalCommandLine { set; }
+
+-    }
+-    public class StartupEventArgs : CancelEventArgs {
+ {
+-        public StartupEventArgs(ReadOnlyCollection<string> args);
+
+-        public ReadOnlyCollection<string> CommandLine { get; }
+
+-    }
+-    public class StartupNextInstanceEventArgs : EventArgs {
+ {
+-        public StartupNextInstanceEventArgs(ReadOnlyCollection<string> args, bool bringToForegroundFlag);
+
+-        public bool BringToForeground { get; set; }
+
+-        public ReadOnlyCollection<string> CommandLine { get; }
+
+-    }
+-    public class UnhandledExceptionEventArgs : ThreadExceptionEventArgs {
+ {
+-        public UnhandledExceptionEventArgs(bool exitApplication, Exception exception);
+
+-        public bool ExitApplication { get; set; }
+
+-    }
+-    public class User {
+ {
+-        public User();
+
+-        public IPrincipal CurrentPrincipal { get; set; }
+
+-        protected virtual IPrincipal InternalPrincipal { get; set; }
+
+-        public bool IsAuthenticated { get; }
+
+-        public string Name { get; }
+
+-        public bool IsInRole(string role);
+
+-    }
+-}
+```
+
diff --git a/release-notes/3.0/preview/api-diff/preview9/.Net/3.0-preview9_Microsoft.VisualBasic.Devices.md b/release-notes/3.0/preview/api-diff/preview9/.Net/3.0-preview9_Microsoft.VisualBasic.Devices.md
new file mode 100644
index 00000000..33fcad4b
--- /dev/null
+++ b/release-notes/3.0/preview/api-diff/preview9/.Net/3.0-preview9_Microsoft.VisualBasic.Devices.md
@@ -0,0 +1,102 @@
+# Microsoft.VisualBasic.Devices
+
+``` diff
+-namespace Microsoft.VisualBasic.Devices {
+ {
+-    public class Audio {
+ {
+-        public Audio();
+
+-    }
+-    public class Clock {
+ {
+-        public Clock();
+
+-        public DateTime GmtTime { get; }
+
+-        public DateTime LocalTime { get; }
+
+-        public int TickCount { get; }
+
+-    }
+-    public class Computer : ServerComputer {
+ {
+-        public Computer();
+
+-        public Audio Audio { get; }
+
+-        public ClipboardProxy Clipboard { get; }
+
+-        public Keyboard Keyboard { get; }
+
+-        public Mouse Mouse { get; }
+
+-        public Ports Ports { get; }
+
+-    }
+-    public class ComputerInfo {
+ {
+-        public ComputerInfo();
+
+-        public ulong AvailablePhysicalMemory { get; }
+
+-        public ulong AvailableVirtualMemory { get; }
+
+-        public CultureInfo InstalledUICulture { get; }
+
+-        public string OSPlatform { get; }
+
+-        public string OSVersion { get; }
+
+-        public ulong TotalPhysicalMemory { get; }
+
+-        public ulong TotalVirtualMemory { get; }
+
+-    }
+-    public class Keyboard {
+ {
+-        public Keyboard();
+
+-    }
+-    public class Mouse {
+ {
+-        public Mouse();
+
+-    }
+-    public class Network {
+ {
+-        public Network();
+
+-    }
+-    public class NetworkAvailableEventArgs : EventArgs {
+ {
+-        public NetworkAvailableEventArgs(bool networkAvailable);
+
+-        public bool IsNetworkAvailable { get; }
+
+-    }
+-    public class Ports {
+ {
+-        public Ports();
+
+-    }
+-    public class ServerComputer {
+ {
+-        public ServerComputer();
+
+-        public Clock Clock { get; }
+
+-        public FileSystemProxy FileSystem { get; }
+
+-        public ComputerInfo Info { get; }
+
+-        public string Name { get; }
+
+-        public Network Network { get; }
+
+-        public RegistryProxy Registry { get; }
+
+-    }
+-}
+```
+
diff --git a/release-notes/3.0/preview/api-diff/preview9/.Net/3.0-preview9_Microsoft.VisualBasic.MyServices.md b/release-notes/3.0/preview/api-diff/preview9/.Net/3.0-preview9_Microsoft.VisualBasic.MyServices.md
new file mode 100644
index 00000000..e629b712
--- /dev/null
+++ b/release-notes/3.0/preview/api-diff/preview9/.Net/3.0-preview9_Microsoft.VisualBasic.MyServices.md
@@ -0,0 +1,148 @@
+# Microsoft.VisualBasic.MyServices
+
+``` diff
+-namespace Microsoft.VisualBasic.MyServices {
+ {
+-    public class ClipboardProxy
+
+-    public class FileSystemProxy {
+ {
+-        public string CurrentDirectory { get; set; }
+
+-        public ReadOnlyCollection<DriveInfo> Drives { get; }
+
+-        public SpecialDirectoriesProxy SpecialDirectories { get; }
+
+-        public string CombinePath(string baseDirectory, string relativePath);
+
+-        public void CopyDirectory(string sourceDirectoryName, string destinationDirectoryName);
+
+-        public void CopyDirectory(string sourceDirectoryName, string destinationDirectoryName, UIOption showUI);
+
+-        public void CopyDirectory(string sourceDirectoryName, string destinationDirectoryName, UIOption showUI, UICancelOption onUserCancel);
+
+-        public void CopyDirectory(string sourceDirectoryName, string destinationDirectoryName, bool overwrite);
+
+-        public void CopyFile(string sourceFileName, string destinationFileName);
+
+-        public void CopyFile(string sourceFileName, string destinationFileName, UIOption showUI);
+
+-        public void CopyFile(string sourceFileName, string destinationFileName, UIOption showUI, UICancelOption onUserCancel);
+
+-        public void CopyFile(string sourceFileName, string destinationFileName, bool overwrite);
+
+-        public void CreateDirectory(string directory);
+
+-        public void DeleteDirectory(string directory, DeleteDirectoryOption onDirectoryNotEmpty);
+
+-        public void DeleteDirectory(string directory, UIOption showUI, RecycleOption recycle);
+
+-        public void DeleteDirectory(string directory, UIOption showUI, RecycleOption recycle, UICancelOption onUserCancel);
+
+-        public void DeleteFile(string file);
+
+-        public void DeleteFile(string file, UIOption showUI, RecycleOption recycle);
+
+-        public void DeleteFile(string file, UIOption showUI, RecycleOption recycle, UICancelOption onUserCancel);
+
+-        public bool DirectoryExists(string directory);
+
+-        public bool FileExists(string file);
+
+-        public ReadOnlyCollection<string> FindInFiles(string directory, string containsText, bool ignoreCase, SearchOption searchType);
+
+-        public ReadOnlyCollection<string> FindInFiles(string directory, string containsText, bool ignoreCase, SearchOption searchType, params string[] fileWildcards);
+
+-        public ReadOnlyCollection<string> GetDirectories(string directory);
+
+-        public ReadOnlyCollection<string> GetDirectories(string directory, SearchOption searchType, params string[] wildcards);
+
+-        public DirectoryInfo GetDirectoryInfo(string directory);
+
+-        public DriveInfo GetDriveInfo(string drive);
+
+-        public FileInfo GetFileInfo(string file);
+
+-        public ReadOnlyCollection<string> GetFiles(string directory);
+
+-        public ReadOnlyCollection<string> GetFiles(string directory, SearchOption searchType, params string[] wildcards);
+
+-        public string GetName(string path);
+
+-        public string GetParentPath(string path);
+
+-        public string GetTempFileName();
+
+-        public void MoveDirectory(string sourceDirectoryName, string destinationDirectoryName);
+
+-        public void MoveDirectory(string sourceDirectoryName, string destinationDirectoryName, UIOption showUI);
+
+-        public void MoveDirectory(string sourceDirectoryName, string destinationDirectoryName, UIOption showUI, UICancelOption onUserCancel);
+
+-        public void MoveDirectory(string sourceDirectoryName, string destinationDirectoryName, bool overwrite);
+
+-        public void MoveFile(string sourceFileName, string destinationFileName);
+
+-        public void MoveFile(string sourceFileName, string destinationFileName, UIOption showUI);
+
+-        public void MoveFile(string sourceFileName, string destinationFileName, UIOption showUI, UICancelOption onUserCancel);
+
+-        public void MoveFile(string sourceFileName, string destinationFileName, bool overwrite);
+
+-        public TextFieldParser OpenTextFieldParser(string file);
+
+-        public TextFieldParser OpenTextFieldParser(string file, params int[] fieldWidths);
+
+-        public TextFieldParser OpenTextFieldParser(string file, params string[] delimiters);
+
+-        public StreamReader OpenTextFileReader(string file);
+
+-        public StreamReader OpenTextFileReader(string file, Encoding encoding);
+
+-        public StreamWriter OpenTextFileWriter(string file, bool append);
+
+-        public StreamWriter OpenTextFileWriter(string file, bool append, Encoding encoding);
+
+-        public byte[] ReadAllBytes(string file);
+
+-        public string ReadAllText(string file);
+
+-        public string ReadAllText(string file, Encoding encoding);
+
+-        public void RenameDirectory(string directory, string newName);
+
+-        public void RenameFile(string file, string newName);
+
+-        public void WriteAllBytes(string file, byte[] data, bool append);
+
+-        public void WriteAllText(string file, string text, bool append);
+
+-        public void WriteAllText(string file, string text, bool append, Encoding encoding);
+
+-    }
+-    public class RegistryProxy
+
+-    public class SpecialDirectoriesProxy {
+ {
+-        public string AllUsersApplicationData { get; }
+
+-        public string CurrentUserApplicationData { get; }
+
+-        public string Desktop { get; }
+
+-        public string MyDocuments { get; }
+
+-        public string MyMusic { get; }
+
+-        public string MyPictures { get; }
+
+-        public string ProgramFiles { get; }
+
+-        public string Programs { get; }
+
+-        public string Temp { get; }
+
+-    }
+-}
+```
+
diff --git a/release-notes/3.0/preview/api-diff/preview9/.Net/3.0-preview9_System.Net.Sockets.md b/release-notes/3.0/preview/api-diff/preview9/.Net/3.0-preview9_System.Net.Sockets.md
new file mode 100644
index 00000000..b2b3ac1d
--- /dev/null
+++ b/release-notes/3.0/preview/api-diff/preview9/.Net/3.0-preview9_System.Net.Sockets.md
@@ -0,0 +1,23 @@
+# System.Net.Sockets
+
+``` diff
+ namespace System.Net.Sockets {
+     public enum AddressFamily {
+-        ControllerAreaNetwork = 32,
++        ControllerAreaNetwork = 65537,
+-        Netlink = 30,
+
+-        Packet = 31,
++        Packet = 65536,
+     }
+     public enum ProtocolFamily {
+-        ControllerAreaNetwork = 32,
++        ControllerAreaNetwork = 65537,
+-        Netlink = 30,
+
+-        Packet = 31,
++        Packet = 65536,
+     }
+ }
+```
+
diff --git a/release-notes/3.0/preview/api-diff/preview9/.Net/3.0-preview9_System.Text.Encodings.Web.md b/release-notes/3.0/preview/api-diff/preview9/.Net/3.0-preview9_System.Text.Encodings.Web.md
new file mode 100644
index 00000000..6850edfd
--- /dev/null
+++ b/release-notes/3.0/preview/api-diff/preview9/.Net/3.0-preview9_System.Text.Encodings.Web.md
@@ -0,0 +1,10 @@
+# System.Text.Encodings.Web
+
+``` diff
+ namespace System.Text.Encodings.Web {
+     public abstract class TextEncoder {
++        public virtual OperationStatus Encode(ReadOnlySpan<char> source, Span<char> destination, out int charsConsumed, out int charsWritten, bool isFinalBlock = true);
+     }
+ }
+```
+
diff --git a/release-notes/3.0/preview/api-diff/preview9/.Net/3.0-preview9_System.Text.Json.md b/release-notes/3.0/preview/api-diff/preview9/.Net/3.0-preview9_System.Text.Json.md
new file mode 100644
index 00000000..fcf57ed0
--- /dev/null
+++ b/release-notes/3.0/preview/api-diff/preview9/.Net/3.0-preview9_System.Text.Json.md
@@ -0,0 +1,17 @@
+# System.Text.Json
+
+``` diff
+ namespace System.Text.Json {
+     public static class JsonSerializer {
+-        public static string Serialize(object value, Type type, JsonSerializerOptions options = null);
++        public static string Serialize(object value, Type inputType, JsonSerializerOptions options = null);
+-        public static void Serialize(Utf8JsonWriter writer, object value, Type type, JsonSerializerOptions options = null);
++        public static void Serialize(Utf8JsonWriter writer, object value, Type inputType, JsonSerializerOptions options = null);
+-        public static Task SerializeAsync(Stream utf8Json, object value, Type type, JsonSerializerOptions options = null, CancellationToken cancellationToken = default(CancellationToken));
++        public static Task SerializeAsync(Stream utf8Json, object value, Type inputType, JsonSerializerOptions options = null, CancellationToken cancellationToken = default(CancellationToken));
+-        public static byte[] SerializeToUtf8Bytes(object value, Type type, JsonSerializerOptions options = null);
++        public static byte[] SerializeToUtf8Bytes(object value, Type inputType, JsonSerializerOptions options = null);
+     }
+ }
+```
+
diff --git a/release-notes/3.0/preview/api-diff/preview9/.Net/standalone-packages/3.0-preview9-standalone-packages.md b/release-notes/3.0/preview/api-diff/preview9/.Net/standalone-packages/3.0-preview9-standalone-packages.md
new file mode 100644
index 00000000..356f5f54
--- /dev/null
+++ b/release-notes/3.0/preview/api-diff/preview9/.Net/standalone-packages/3.0-preview9-standalone-packages.md
@@ -0,0 +1,6 @@
+# API Difference netcoreapp3.0-preview8 vs netcoreapp3.0-preview9
+
+API listing follows standard diff formatting. Lines preceded by a '+' are
+additions and a '-' indicates removal.
+
+
diff --git a/release-notes/3.0/preview/api-diff/preview9/Asp.Net/3.0-preview9.md b/release-notes/3.0/preview/api-diff/preview9/Asp.Net/3.0-preview9.md
new file mode 100644
index 00000000..87e5df6b
--- /dev/null
+++ b/release-notes/3.0/preview/api-diff/preview9/Asp.Net/3.0-preview9.md
@@ -0,0 +1,24 @@
+# API Difference netcoreapp3.0-preview8 vs netcoreapp3.0-preview9
+
+API listing follows standard diff formatting. Lines preceded by a '+' are
+additions and a '-' indicates removal.
+
+* [Microsoft.AspNetCore.Builder](3.0-preview9_Microsoft.AspNetCore.Builder.md)
+* [Microsoft.AspNetCore.Components](3.0-preview9_Microsoft.AspNetCore.Components.md)
+* [Microsoft.AspNetCore.Components.Authorization](3.0-preview9_Microsoft.AspNetCore.Components.Authorization.md)
+* [Microsoft.AspNetCore.Components.Forms](3.0-preview9_Microsoft.AspNetCore.Components.Forms.md)
+* [Microsoft.AspNetCore.Components.Rendering](3.0-preview9_Microsoft.AspNetCore.Components.Rendering.md)
+* [Microsoft.AspNetCore.Components.RenderTree](3.0-preview9_Microsoft.AspNetCore.Components.RenderTree.md)
+* [Microsoft.AspNetCore.Components.Routing](3.0-preview9_Microsoft.AspNetCore.Components.Routing.md)
+* [Microsoft.AspNetCore.Components.Server](3.0-preview9_Microsoft.AspNetCore.Components.Server.md)
+* [Microsoft.AspNetCore.Components.Server.Circuits](3.0-preview9_Microsoft.AspNetCore.Components.Server.Circuits.md)
+* [Microsoft.AspNetCore.Components.Web](3.0-preview9_Microsoft.AspNetCore.Components.Web.md)
+* [Microsoft.AspNetCore.Mvc](3.0-preview9_Microsoft.AspNetCore.Mvc.md)
+* [Microsoft.AspNetCore.Mvc.Formatters](3.0-preview9_Microsoft.AspNetCore.Mvc.Formatters.md)
+* [Microsoft.AspNetCore.Mvc.Infrastructure](3.0-preview9_Microsoft.AspNetCore.Mvc.Infrastructure.md)
+* [Microsoft.AspNetCore.Mvc.ModelBinding](3.0-preview9_Microsoft.AspNetCore.Mvc.ModelBinding.md)
+* [Microsoft.AspNetCore.Mvc.RazorPages](3.0-preview9_Microsoft.AspNetCore.Mvc.RazorPages.md)
+* [Microsoft.AspNetCore.Mvc.Rendering](3.0-preview9_Microsoft.AspNetCore.Mvc.Rendering.md)
+* [Microsoft.JSInterop](3.0-preview9_Microsoft.JSInterop.md)
+* [Microsoft.JSInterop.Infrastructure](3.0-preview9_Microsoft.JSInterop.Infrastructure.md)
+
diff --git a/release-notes/3.0/preview/api-diff/preview9/Asp.Net/3.0-preview9_Microsoft.AspNetCore.Builder.md b/release-notes/3.0/preview/api-diff/preview9/Asp.Net/3.0-preview9_Microsoft.AspNetCore.Builder.md
new file mode 100644
index 00000000..ee2217dd
--- /dev/null
+++ b/release-notes/3.0/preview/api-diff/preview9/Asp.Net/3.0-preview9_Microsoft.AspNetCore.Builder.md
@@ -0,0 +1,32 @@
+# Microsoft.AspNetCore.Builder
+
+``` diff
+ namespace Microsoft.AspNetCore.Builder {
+-    public static class ComponentEndpointConventionBuilderExtensions {
+ {
+-        public static ComponentEndpointConventionBuilder AddComponent(this ComponentEndpointConventionBuilder builder, Type componentType, string selector);
+
+-    }
+     public static class ComponentEndpointRouteBuilderExtensions {
++        public static ComponentEndpointConventionBuilder MapBlazorHub(this IEndpointRouteBuilder endpoints, string path);
++        public static ComponentEndpointConventionBuilder MapBlazorHub(this IEndpointRouteBuilder endpoints, string path, Action<HttpConnectionDispatcherOptions> configureOptions);
+-        public static ComponentEndpointConventionBuilder MapBlazorHub(this IEndpointRouteBuilder endpoints, Type type, string selector);
+
+-        public static ComponentEndpointConventionBuilder MapBlazorHub(this IEndpointRouteBuilder endpoints, Type type, string selector, Action<HttpConnectionDispatcherOptions> configureOptions);
+
+-        public static ComponentEndpointConventionBuilder MapBlazorHub(this IEndpointRouteBuilder endpoints, Type componentType, string selector, string path);
+
+-        public static ComponentEndpointConventionBuilder MapBlazorHub(this IEndpointRouteBuilder endpoints, Type componentType, string selector, string path, Action<HttpConnectionDispatcherOptions> configureOptions);
+
+-        public static ComponentEndpointConventionBuilder MapBlazorHub<TComponent>(this IEndpointRouteBuilder endpoints, string selector) where TComponent : IComponent;
+
+-        public static ComponentEndpointConventionBuilder MapBlazorHub<TComponent>(this IEndpointRouteBuilder endpoints, string selector, Action<HttpConnectionDispatcherOptions> configureOptions) where TComponent : IComponent;
+
+-        public static ComponentEndpointConventionBuilder MapBlazorHub<TComponent>(this IEndpointRouteBuilder endpoints, string selector, string path) where TComponent : IComponent;
+
+-        public static ComponentEndpointConventionBuilder MapBlazorHub<TComponent>(this IEndpointRouteBuilder endpoints, string selector, string path, Action<HttpConnectionDispatcherOptions> configureOptions) where TComponent : IComponent;
+
+     }
+ }
+```
+
diff --git a/release-notes/3.0/preview/api-diff/preview9/Asp.Net/3.0-preview9_Microsoft.AspNetCore.Components.Authorization.md b/release-notes/3.0/preview/api-diff/preview9/Asp.Net/3.0-preview9_Microsoft.AspNetCore.Components.Authorization.md
new file mode 100644
index 00000000..fde1ee94
--- /dev/null
+++ b/release-notes/3.0/preview/api-diff/preview9/Asp.Net/3.0-preview9_Microsoft.AspNetCore.Components.Authorization.md
@@ -0,0 +1,51 @@
+# Microsoft.AspNetCore.Components.Authorization
+
+``` diff
++namespace Microsoft.AspNetCore.Components.Authorization {
++    public class AuthenticationState {
++        public AuthenticationState(ClaimsPrincipal user);
++        public ClaimsPrincipal User { get; }
++    }
++    public delegate void AuthenticationStateChangedHandler(Task<AuthenticationState> task);
++    public abstract class AuthenticationStateProvider {
++        protected AuthenticationStateProvider();
++        public event AuthenticationStateChangedHandler AuthenticationStateChanged;
++        public abstract Task<AuthenticationState> GetAuthenticationStateAsync();
++        protected void NotifyAuthenticationStateChanged(Task<AuthenticationState> task);
++    }
++    public sealed class AuthorizeRouteView : RouteView {
++        public AuthorizeRouteView();
++        public RenderFragment Authorizing { get; set; }
++        public RenderFragment<AuthenticationState> NotAuthorized { get; set; }
++        protected override void Render(RenderTreeBuilder builder);
++    }
++    public class AuthorizeView : AuthorizeViewCore {
++        public AuthorizeView();
++        public string Policy { get; set; }
++        public string Roles { get; set; }
++        protected override IAuthorizeData[] GetAuthorizeData();
++    }
++    public abstract class AuthorizeViewCore : ComponentBase {
++        protected AuthorizeViewCore();
++        public RenderFragment<AuthenticationState> Authorized { get; set; }
++        public RenderFragment Authorizing { get; set; }
++        public RenderFragment<AuthenticationState> ChildContent { get; set; }
++        public RenderFragment<AuthenticationState> NotAuthorized { get; set; }
++        public object Resource { get; set; }
++        protected override void BuildRenderTree(RenderTreeBuilder builder);
++        protected abstract IAuthorizeData[] GetAuthorizeData();
++        protected override Task OnParametersSetAsync();
++    }
++    public class CascadingAuthenticationState : ComponentBase, IDisposable {
++        public CascadingAuthenticationState();
++        public RenderFragment ChildContent { get; set; }
++        protected override void BuildRenderTree(RenderTreeBuilder __builder);
++        protected override void OnInitialized();
++        void System.IDisposable.Dispose();
++    }
++    public interface IHostEnvironmentAuthenticationStateProvider {
++        void SetAuthenticationState(Task<AuthenticationState> authenticationStateTask);
++    }
++}
+```
+
diff --git a/release-notes/3.0/preview/api-diff/preview9/Asp.Net/3.0-preview9_Microsoft.AspNetCore.Components.Forms.md b/release-notes/3.0/preview/api-diff/preview9/Asp.Net/3.0-preview9_Microsoft.AspNetCore.Components.Forms.md
new file mode 100644
index 00000000..d7a26fe3
--- /dev/null
+++ b/release-notes/3.0/preview/api-diff/preview9/Asp.Net/3.0-preview9_Microsoft.AspNetCore.Components.Forms.md
@@ -0,0 +1,217 @@
+# Microsoft.AspNetCore.Components.Forms
+
+``` diff
+ namespace Microsoft.AspNetCore.Components.Forms {
+     public sealed class EditContext {
++        public IEnumerable<string> GetValidationMessages(Expression<Func<object>> accessor);
++        public bool IsModified(Expression<Func<object>> accessor);
+     }
+-    public static class EditContextExpressionExtensions {
+ {
+-        public static IEnumerable<string> GetValidationMessages(this EditContext editContext, Expression<Func<object>> accessor);
+
+-        public static bool IsModified(this EditContext editContext, Expression<Func<object>> accessor);
+
+-    }
+     public static class EditContextFieldClassExtensions {
+-        public static string FieldClass(this EditContext editContext, in FieldIdentifier fieldIdentifier);
+
+-        public static string FieldClass<TField>(this EditContext editContext, Expression<Func<TField>> accessor);
+
++        public static string FieldCssClass(this EditContext editContext, in FieldIdentifier fieldIdentifier);
++        public static string FieldCssClass<TField>(this EditContext editContext, Expression<Func<TField>> accessor);
+     }
+     public class EditForm : ComponentBase {
++        protected override void BuildRenderTree(RenderTreeBuilder builder);
+-        protected override void BuildRenderTree(RenderTreeBuilder builder);
+
+     }
+-    public sealed class FieldChangedEventArgs {
++    public sealed class FieldChangedEventArgs : EventArgs {
++        public FieldChangedEventArgs(in FieldIdentifier fieldIdentifier);
+     }
+-    public readonly struct FieldIdentifier {
++    public readonly struct FieldIdentifier : IEquatable<FieldIdentifier> {
+-        public static FieldIdentifier Create<T>(Expression<Func<T>> accessor);
+
++        public static FieldIdentifier Create<TField>(Expression<Func<TField>> accessor);
++        public bool Equals(FieldIdentifier otherIdentifier);
+     }
+-    public abstract class InputBase<T> : ComponentBase {
+ {
+-        protected InputBase();
+
+-        public IReadOnlyDictionary<string, object> AdditionalAttributes { get; set; }
+
+-        protected string CssClass { get; }
+
+-        protected T CurrentValue { get; set; }
+
+-        protected string CurrentValueAsString { get; set; }
+
+-        protected EditContext EditContext { get; set; }
+
+-        protected string FieldClass { get; }
+
+-        protected FieldIdentifier FieldIdentifier { get; set; }
+
+-        public T Value { get; set; }
+
+-        public EventCallback<T> ValueChanged { get; set; }
+
+-        public Expression<Func<T>> ValueExpression { get; set; }
+
+-        protected virtual string FormatValueAsString(T value);
+
+-        public override Task SetParametersAsync(ParameterView parameters);
+
+-        protected abstract bool TryParseValueFromString(string value, out T result, out string validationErrorMessage);
+
+-    }
++    public abstract class InputBase<TValue> : ComponentBase {
++        protected InputBase();
++        public IReadOnlyDictionary<string, object> AdditionalAttributes { get; set; }
++        protected string CssClass { get; }
++        protected TValue CurrentValue { get; set; }
++        protected string CurrentValueAsString { get; set; }
++        protected EditContext EditContext { get; set; }
++        protected FieldIdentifier FieldIdentifier { get; set; }
++        public TValue Value { get; set; }
++        public EventCallback<TValue> ValueChanged { get; set; }
++        public Expression<Func<TValue>> ValueExpression { get; set; }
++        protected virtual string FormatValueAsString(TValue value);
++        public override Task SetParametersAsync(ParameterView parameters);
++        protected abstract bool TryParseValueFromString(string value, out TValue result, out string validationErrorMessage);
++    }
+     public class InputCheckbox : InputBase<bool> {
++        protected override void BuildRenderTree(RenderTreeBuilder builder);
+-        protected override void BuildRenderTree(RenderTreeBuilder builder);
+
+     }
+-    public class InputDate<T> : InputBase<T> {
+ {
+-        public InputDate();
+
+-        public string ParsingErrorMessage { get; set; }
+
+-        protected override void BuildRenderTree(RenderTreeBuilder builder);
+
+-        protected override string FormatValueAsString(T value);
+
+-        protected override bool TryParseValueFromString(string value, out T result, out string validationErrorMessage);
+
+-    }
++    public class InputDate<TValue> : InputBase<TValue> {
++        public InputDate();
++        public string ParsingErrorMessage { get; set; }
++        protected override void BuildRenderTree(RenderTreeBuilder builder);
++        protected override string FormatValueAsString(TValue value);
++        protected override bool TryParseValueFromString(string value, out TValue result, out string validationErrorMessage);
++    }
+-    public class InputNumber<T> : InputBase<T> {
+ {
+-        public InputNumber();
+
+-        public string ParsingErrorMessage { get; set; }
+
+-        protected override void BuildRenderTree(RenderTreeBuilder builder);
+
+-        protected override string FormatValueAsString(T value);
+
+-        protected override bool TryParseValueFromString(string value, out T result, out string validationErrorMessage);
+
+-    }
++    public class InputNumber<TValue> : InputBase<TValue> {
++        public InputNumber();
++        public string ParsingErrorMessage { get; set; }
++        protected override void BuildRenderTree(RenderTreeBuilder builder);
++        protected override string FormatValueAsString(TValue value);
++        protected override bool TryParseValueFromString(string value, out TValue result, out string validationErrorMessage);
++    }
+-    public class InputSelect<T> : InputBase<T> {
+ {
+-        public InputSelect();
+
+-        public RenderFragment ChildContent { get; set; }
+
+-        protected override void BuildRenderTree(RenderTreeBuilder builder);
+
+-        protected override bool TryParseValueFromString(string value, out T result, out string validationErrorMessage);
+
+-    }
++    public class InputSelect<TValue> : InputBase<TValue> {
++        public InputSelect();
++        public RenderFragment ChildContent { get; set; }
++        protected override void BuildRenderTree(RenderTreeBuilder builder);
++        protected override bool TryParseValueFromString(string value, out TValue result, out string validationErrorMessage);
++    }
+     public class InputText : InputBase<string> {
++        protected override void BuildRenderTree(RenderTreeBuilder builder);
+-        protected override void BuildRenderTree(RenderTreeBuilder builder);
+
+     }
+     public class InputTextArea : InputBase<string> {
++        protected override void BuildRenderTree(RenderTreeBuilder builder);
+-        protected override void BuildRenderTree(RenderTreeBuilder builder);
+
+     }
+-    public class ValidationMessage<T> : ComponentBase, IDisposable {
+ {
+-        public ValidationMessage();
+
+-        public IReadOnlyDictionary<string, object> AdditionalAttributes { get; set; }
+
+-        public Expression<Func<T>> For { get; set; }
+
+-        protected override void BuildRenderTree(RenderTreeBuilder builder);
+
+-        protected override void OnParametersSet();
+
+-        void System.IDisposable.Dispose();
+
+-    }
++    public class ValidationMessage<TValue> : ComponentBase, IDisposable {
++        public ValidationMessage();
++        public IReadOnlyDictionary<string, object> AdditionalAttributes { get; set; }
++        public Expression<Func<TValue>> For { get; set; }
++        protected override void BuildRenderTree(RenderTreeBuilder builder);
++        protected virtual void Dispose(bool disposing);
++        protected override void OnParametersSet();
++        void System.IDisposable.Dispose();
++    }
+     public sealed class ValidationMessageStore {
++        public void Add(in FieldIdentifier fieldIdentifier, IEnumerable<string> messages);
++        public void Add(Expression<Func<object>> accessor, IEnumerable<string> messages);
++        public void Add(Expression<Func<object>> accessor, string message);
+-        public void AddRange(in FieldIdentifier fieldIdentifier, IEnumerable<string> messages);
+
++        public void Clear(Expression<Func<object>> accessor);
+     }
+-    public static class ValidationMessageStoreExpressionExtensions {
+ {
+-        public static void Add(this ValidationMessageStore store, Expression<Func<object>> accessor, string message);
+
+-        public static void AddRange(this ValidationMessageStore store, Expression<Func<object>> accessor, IEnumerable<string> messages);
+
+-        public static void Clear(this ValidationMessageStore store, Expression<Func<object>> accessor);
+
+-    }
+-    public sealed class ValidationRequestedEventArgs {
++    public sealed class ValidationRequestedEventArgs : EventArgs {
++        public static readonly ValidationRequestedEventArgs Empty;
++        public ValidationRequestedEventArgs();
+     }
+-    public sealed class ValidationStateChangedEventArgs {
++    public sealed class ValidationStateChangedEventArgs : EventArgs {
++        public static readonly ValidationStateChangedEventArgs Empty;
++        public ValidationStateChangedEventArgs();
+     }
+     public class ValidationSummary : ComponentBase, IDisposable {
++        protected override void BuildRenderTree(RenderTreeBuilder builder);
+-        protected override void BuildRenderTree(RenderTreeBuilder builder);
+
++        protected virtual void Dispose(bool disposing);
+     }
+ }
+```
+
diff --git a/release-notes/3.0/preview/api-diff/preview9/Asp.Net/3.0-preview9_Microsoft.AspNetCore.Components.RenderTree.md b/release-notes/3.0/preview/api-diff/preview9/Asp.Net/3.0-preview9_Microsoft.AspNetCore.Components.RenderTree.md
new file mode 100644
index 00000000..594c8ce9
--- /dev/null
+++ b/release-notes/3.0/preview/api-diff/preview9/Asp.Net/3.0-preview9_Microsoft.AspNetCore.Components.RenderTree.md
@@ -0,0 +1,102 @@
+# Microsoft.AspNetCore.Components.RenderTree
+
+``` diff
+ namespace Microsoft.AspNetCore.Components.RenderTree {
++    public class EventFieldInfo {
++        public EventFieldInfo();
++        public int ComponentId { get; set; }
++        public object FieldValue { get; set; }
++    }
++    public readonly struct RenderBatch {
++        public ArrayRange<int> DisposedComponentIDs { get; }
++        public ArrayRange<ulong> DisposedEventHandlerIDs { get; }
++        public ArrayRange<RenderTreeFrame> ReferenceFrames { get; }
++        public ArrayRange<RenderTreeDiff> UpdatedComponents { get; }
++    }
++    public abstract class Renderer : IDisposable {
++        public Renderer(IServiceProvider serviceProvider, ILoggerFactory loggerFactory);
++        public abstract Dispatcher Dispatcher { get; }
++        public event UnhandledExceptionEventHandler UnhandledSynchronizationException;
++        protected internal int AssignRootComponentId(IComponent component);
++        public virtual Task DispatchEventAsync(ulong eventHandlerId, EventFieldInfo fieldInfo, EventArgs eventArgs);
++        public void Dispose();
++        protected virtual void Dispose(bool disposing);
++        protected ArrayRange<RenderTreeFrame> GetCurrentRenderTreeFrames(int componentId);
++        protected abstract void HandleException(Exception exception);
++        protected IComponent InstantiateComponent(Type componentType);
++        protected virtual void ProcessPendingRender();
++        protected Task RenderRootComponentAsync(int componentId);
++        protected Task RenderRootComponentAsync(int componentId, ParameterView initialParameters);
++        protected abstract Task UpdateDisplayAsync(in RenderBatch renderBatch);
++    }
+-    public sealed class RenderTreeBuilder : IDisposable {
+ {
+-        public RenderTreeBuilder();
+
+-        public void AddAttribute(int sequence, in RenderTreeFrame frame);
+
+-        public void AddAttribute(int sequence, string name, EventCallback value);
+
+-        public void AddAttribute(int sequence, string name, bool value);
+
+-        public void AddAttribute(int sequence, string name, MulticastDelegate value);
+
+-        public void AddAttribute(int sequence, string name, object value);
+
+-        public void AddAttribute(int sequence, string name, string value);
+
+-        public void AddAttribute<T>(int sequence, string name, EventCallback<T> value);
+
+-        public void AddComponentReferenceCapture(int sequence, Action<object> componentReferenceCaptureAction);
+
+-        public void AddContent(int sequence, MarkupString markupContent);
+
+-        public void AddContent(int sequence, RenderFragment fragment);
+
+-        public void AddContent(int sequence, object textContent);
+
+-        public void AddContent(int sequence, string textContent);
+
+-        public void AddContent<T>(int sequence, RenderFragment<T> fragment, T value);
+
+-        public void AddElementReferenceCapture(int sequence, Action<ElementReference> elementReferenceCaptureAction);
+
+-        public void AddMarkupContent(int sequence, string markupContent);
+
+-        public void AddMultipleAttributes(int sequence, IEnumerable<KeyValuePair<string, object>> attributes);
+
+-        public void Clear();
+
+-        public void CloseComponent();
+
+-        public void CloseElement();
+
+-        public void CloseRegion();
+
+-        public ArrayRange<RenderTreeFrame> GetFrames();
+
+-        public void OpenComponent(int sequence, Type componentType);
+
+-        public void OpenComponent<TComponent>(int sequence) where TComponent : IComponent;
+
+-        public void OpenElement(int sequence, string elementName);
+
+-        public void OpenRegion(int sequence);
+
+-        public void SetKey(object value);
+
+-        public void SetUpdatesAttributeName(string updatesAttributeName);
+
+-        void System.IDisposable.Dispose();
+
+-    }
++    public sealed class WebEventDescriptor {
++        public WebEventDescriptor();
++        public int BrowserRendererId { get; set; }
++        public string EventArgsType { get; set; }
++        public EventFieldInfo EventFieldInfo { get; set; }
++        public ulong EventHandlerId { get; set; }
++    }
+ }
+```
+
diff --git a/release-notes/3.0/preview/api-diff/preview9/Asp.Net/3.0-preview9_Microsoft.AspNetCore.Components.Rendering.md b/release-notes/3.0/preview/api-diff/preview9/Asp.Net/3.0-preview9_Microsoft.AspNetCore.Components.Rendering.md
new file mode 100644
index 00000000..76808925
--- /dev/null
+++ b/release-notes/3.0/preview/api-diff/preview9/Asp.Net/3.0-preview9_Microsoft.AspNetCore.Components.Rendering.md
@@ -0,0 +1,109 @@
+# Microsoft.AspNetCore.Components.Rendering
+
+``` diff
+ namespace Microsoft.AspNetCore.Components.Rendering {
+-    public readonly struct ComponentRenderedText {
+ {
+-        public int ComponentId { get; }
+
+-        public IEnumerable<string> Tokens { get; }
+
+-    }
+-    public class EventFieldInfo {
+ {
+-        public EventFieldInfo();
+
+-        public int ComponentId { get; set; }
+
+-        public object FieldValue { get; set; }
+
+-    }
+-    public class HtmlRenderer : Renderer {
+ {
+-        public HtmlRenderer(IServiceProvider serviceProvider, ILoggerFactory loggerFactory, Func<string, string> htmlEncoder);
+
+-        public override Dispatcher Dispatcher { get; }
+
+-        protected override void HandleException(Exception exception);
+
+-        public Task<ComponentRenderedText> RenderComponentAsync(Type componentType, ParameterView initialParameters);
+
+-        public Task<ComponentRenderedText> RenderComponentAsync<TComponent>(ParameterView initialParameters) where TComponent : IComponent;
+
+-        protected override Task UpdateDisplayAsync(in RenderBatch renderBatch);
+
+-    }
+-    public readonly struct RenderBatch {
+ {
+-        public ArrayRange<int> DisposedComponentIDs { get; }
+
+-        public ArrayRange<ulong> DisposedEventHandlerIDs { get; }
+
+-        public ArrayRange<RenderTreeFrame> ReferenceFrames { get; }
+
+-        public ArrayRange<RenderTreeDiff> UpdatedComponents { get; }
+
+-    }
+-    public abstract class Renderer : IDisposable {
+ {
+-        public Renderer(IServiceProvider serviceProvider, ILoggerFactory loggerFactory);
+
+-        public abstract Dispatcher Dispatcher { get; }
+
+-        public event UnhandledExceptionEventHandler UnhandledSynchronizationException;
+
+-        protected internal virtual void AddToRenderQueue(int componentId, RenderFragment renderFragment);
+
+-        protected internal int AssignRootComponentId(IComponent component);
+
+-        public virtual Task DispatchEventAsync(ulong eventHandlerId, EventFieldInfo fieldInfo, UIEventArgs eventArgs);
+
+-        public void Dispose();
+
+-        protected virtual void Dispose(bool disposing);
+
+-        protected abstract void HandleException(Exception exception);
+
+-        protected IComponent InstantiateComponent(Type componentType);
+
+-        protected Task RenderRootComponentAsync(int componentId);
+
+-        protected Task RenderRootComponentAsync(int componentId, ParameterView initialParameters);
+
+-        protected abstract Task UpdateDisplayAsync(in RenderBatch renderBatch);
+
+-    }
++    public sealed class RenderTreeBuilder : IDisposable {
++        public RenderTreeBuilder();
++        public void AddAttribute(int sequence, in RenderTreeFrame frame);
++        public void AddAttribute(int sequence, string name, EventCallback value);
++        public void AddAttribute(int sequence, string name, bool value);
++        public void AddAttribute(int sequence, string name, MulticastDelegate value);
++        public void AddAttribute(int sequence, string name, object value);
++        public void AddAttribute(int sequence, string name, string value);
++        public void AddAttribute<TArgument>(int sequence, string name, EventCallback<TArgument> value);
++        public void AddComponentReferenceCapture(int sequence, Action<object> componentReferenceCaptureAction);
++        public void AddContent(int sequence, MarkupString markupContent);
++        public void AddContent(int sequence, RenderFragment fragment);
++        public void AddContent(int sequence, object textContent);
++        public void AddContent(int sequence, string textContent);
++        public void AddContent<TValue>(int sequence, RenderFragment<TValue> fragment, TValue value);
++        public void AddElementReferenceCapture(int sequence, Action<ElementReference> elementReferenceCaptureAction);
++        public void AddMarkupContent(int sequence, string markupContent);
++        public void AddMultipleAttributes(int sequence, IEnumerable<KeyValuePair<string, object>> attributes);
++        public void Clear();
++        public void CloseComponent();
++        public void CloseElement();
++        public void CloseRegion();
++        public ArrayRange<RenderTreeFrame> GetFrames();
++        public void OpenComponent(int sequence, Type componentType);
++        public void OpenComponent<TComponent>(int sequence) where TComponent : IComponent;
++        public void OpenElement(int sequence, string elementName);
++        public void OpenRegion(int sequence);
++        public void SetKey(object value);
++        public void SetUpdatesAttributeName(string updatesAttributeName);
++        void System.IDisposable.Dispose();
++    }
+ }
+```
+
diff --git a/release-notes/3.0/preview/api-diff/preview9/Asp.Net/3.0-preview9_Microsoft.AspNetCore.Components.Routing.md b/release-notes/3.0/preview/api-diff/preview9/Asp.Net/3.0-preview9_Microsoft.AspNetCore.Components.Routing.md
new file mode 100644
index 00000000..3ed45dd9
--- /dev/null
+++ b/release-notes/3.0/preview/api-diff/preview9/Asp.Net/3.0-preview9_Microsoft.AspNetCore.Components.Routing.md
@@ -0,0 +1,30 @@
+# Microsoft.AspNetCore.Components.Routing
+
+``` diff
+ namespace Microsoft.AspNetCore.Components.Routing {
++    public interface IHostEnvironmentNavigationManager {
++        void Initialize(string baseUri, string uri);
++    }
+-    public readonly struct LocationChangedEventArgs
++    public class LocationChangedEventArgs : EventArgs
+     public class NavLink : ComponentBase, IDisposable {
++        protected override void BuildRenderTree(RenderTreeBuilder builder);
+-        protected override void BuildRenderTree(RenderTreeBuilder builder);
+
+     }
+     public class Router : IComponent, IDisposable, IHandleAfterRender {
++        public IEnumerable<Assembly> AdditionalAssemblies { get; set; }
+-        public RenderFragment AuthorizingContent { get; set; }
+
++        public RenderFragment<RouteData> Found { get; set; }
+-        public RenderFragment<AuthenticationState> NotAuthorizedContent { get; set; }
+
++        public RenderFragment NotFound { get; set; }
+-        public RenderFragment NotFoundContent { get; set; }
+
+-        protected virtual void Render(RenderTreeBuilder builder, Type handler, IDictionary<string, object> parameters);
+
+     }
+ }
+```
+
diff --git a/release-notes/3.0/preview/api-diff/preview9/Asp.Net/3.0-preview9_Microsoft.AspNetCore.Components.Server.Circuits.md b/release-notes/3.0/preview/api-diff/preview9/Asp.Net/3.0-preview9_Microsoft.AspNetCore.Components.Server.Circuits.md
new file mode 100644
index 00000000..e1037144
--- /dev/null
+++ b/release-notes/3.0/preview/api-diff/preview9/Asp.Net/3.0-preview9_Microsoft.AspNetCore.Components.Server.Circuits.md
@@ -0,0 +1,20 @@
+# Microsoft.AspNetCore.Components.Server.Circuits
+
+``` diff
+ namespace Microsoft.AspNetCore.Components.Server.Circuits {
+-    public class RemoteUriHelper : UriHelperBase {
+ {
+-        public RemoteUriHelper(ILogger<RemoteUriHelper> logger);
+
+-        public bool HasAttachedJSRuntime { get; }
+
+-        public override void InitializeState(string uriAbsolute, string baseUriAbsolute);
+
+-        protected override void NavigateToCore(string uri, bool forceLoad);
+
+-        public static void NotifyLocationChanged(string uriAbsolute, bool isInterceptedLink);
+
+-    }
+ }
+```
+
diff --git a/release-notes/3.0/preview/api-diff/preview9/Asp.Net/3.0-preview9_Microsoft.AspNetCore.Components.Server.md b/release-notes/3.0/preview/api-diff/preview9/Asp.Net/3.0-preview9_Microsoft.AspNetCore.Components.Server.md
new file mode 100644
index 00000000..fe6ec0a3
--- /dev/null
+++ b/release-notes/3.0/preview/api-diff/preview9/Asp.Net/3.0-preview9_Microsoft.AspNetCore.Components.Server.md
@@ -0,0 +1,43 @@
+# Microsoft.AspNetCore.Components.Server
+
+``` diff
+ namespace Microsoft.AspNetCore.Components.Server {
+     public sealed class CircuitOptions {
++        public int MaxBufferedUnacknowledgedRenderBatches { get; set; }
+     }
+-    public class ComponentPrerenderingContext {
+ {
+-        public ComponentPrerenderingContext();
+
+-        public Type ComponentType { get; set; }
+
+-        public HttpContext Context { get; set; }
+
+-        public ParameterView Parameters { get; set; }
+
+-    }
+-    public sealed class ComponentPrerenderResult {
+ {
+-        public void WriteTo(TextWriter writer);
+
+-    }
+-    public interface IComponentPrerenderer {
+ {
+-        Task<ComponentPrerenderResult> PrerenderComponentAsync(ComponentPrerenderingContext context);
+
+-    }
++    public abstract class RevalidatingServerAuthenticationStateProvider : ServerAuthenticationStateProvider, IDisposable {
++        public RevalidatingServerAuthenticationStateProvider(ILoggerFactory loggerFactory);
++        protected abstract TimeSpan RevalidationInterval { get; }
++        protected virtual void Dispose(bool disposing);
++        void System.IDisposable.Dispose();
++        protected abstract Task<bool> ValidateAuthenticationStateAsync(AuthenticationState authenticationState, CancellationToken cancellationToken);
++    }
++    public class ServerAuthenticationStateProvider : AuthenticationStateProvider, IHostEnvironmentAuthenticationStateProvider {
++        public ServerAuthenticationStateProvider();
++        public override Task<AuthenticationState> GetAuthenticationStateAsync();
++        public void SetAuthenticationState(Task<AuthenticationState> authenticationStateTask);
++    }
+ }
+```
+
diff --git a/release-notes/3.0/preview/api-diff/preview9/Asp.Net/3.0-preview9_Microsoft.AspNetCore.Components.Web.md b/release-notes/3.0/preview/api-diff/preview9/Asp.Net/3.0-preview9_Microsoft.AspNetCore.Components.Web.md
new file mode 100644
index 00000000..a7224644
--- /dev/null
+++ b/release-notes/3.0/preview/api-diff/preview9/Asp.Net/3.0-preview9_Microsoft.AspNetCore.Components.Web.md
@@ -0,0 +1,156 @@
+# Microsoft.AspNetCore.Components.Web
+
+``` diff
+ namespace Microsoft.AspNetCore.Components.Web {
++    public static class BindAttributes
++    public class ClipboardEventArgs : EventArgs {
++        public ClipboardEventArgs();
++        public string Type { get; set; }
++    }
++    public class DataTransfer {
++        public DataTransfer();
++        public string DropEffect { get; set; }
++        public string EffectAllowed { get; set; }
++        public string[] Files { get; set; }
++        public DataTransferItem[] Items { get; set; }
++        public string[] Types { get; set; }
++    }
++    public class DataTransferItem {
++        public DataTransferItem();
++        public string Kind { get; set; }
++        public string Type { get; set; }
++    }
++    public class DragEventArgs : MouseEventArgs {
++        public DragEventArgs();
++        public DataTransfer DataTransfer { get; set; }
++    }
++    public class ErrorEventArgs : EventArgs {
++        public ErrorEventArgs();
++        public int Colno { get; set; }
++        public string Filename { get; set; }
++        public int Lineno { get; set; }
++        public string Message { get; set; }
++        public string Type { get; set; }
++    }
++    public static class EventHandlers
++    public class FocusEventArgs : EventArgs {
++        public FocusEventArgs();
++        public string Type { get; set; }
++    }
++    public class KeyboardEventArgs : EventArgs {
++        public KeyboardEventArgs();
++        public bool AltKey { get; set; }
++        public string Code { get; set; }
++        public bool CtrlKey { get; set; }
++        public string Key { get; set; }
++        public float Location { get; set; }
++        public bool MetaKey { get; set; }
++        public bool Repeat { get; set; }
++        public bool ShiftKey { get; set; }
++        public string Type { get; set; }
++    }
++    public class MouseEventArgs : EventArgs {
++        public MouseEventArgs();
++        public bool AltKey { get; set; }
++        public long Button { get; set; }
++        public long Buttons { get; set; }
++        public double ClientX { get; set; }
++        public double ClientY { get; set; }
++        public bool CtrlKey { get; set; }
++        public long Detail { get; set; }
++        public bool MetaKey { get; set; }
++        public double ScreenX { get; set; }
++        public double ScreenY { get; set; }
++        public bool ShiftKey { get; set; }
++        public string Type { get; set; }
++    }
++    public class PointerEventArgs : MouseEventArgs {
++        public PointerEventArgs();
++        public float Height { get; set; }
++        public bool IsPrimary { get; set; }
++        public long PointerId { get; set; }
++        public string PointerType { get; set; }
++        public float Pressure { get; set; }
++        public float TiltX { get; set; }
++        public float TiltY { get; set; }
++        public float Width { get; set; }
++    }
++    public class ProgressEventArgs : EventArgs {
++        public ProgressEventArgs();
++        public bool LengthComputable { get; set; }
++        public long Loaded { get; set; }
++        public long Total { get; set; }
++        public string Type { get; set; }
++    }
+-    public static class RendererRegistryEventDispatcher {
+ {
+-        public static Task DispatchEvent(RendererRegistryEventDispatcher.BrowserEventDescriptor eventDescriptor, string eventArgsJson);
+
+-        public class BrowserEventDescriptor {
+ {
+-            public BrowserEventDescriptor();
+
+-            public int BrowserRendererId { get; set; }
+
+-            public string EventArgsType { get; set; }
+
+-            public EventFieldInfo EventFieldInfo { get; set; }
+
+-            public ulong EventHandlerId { get; set; }
+
+-        }
+-    }
++    public class TouchEventArgs : EventArgs {
++        public TouchEventArgs();
++        public bool AltKey { get; set; }
++        public TouchPoint[] ChangedTouches { get; set; }
++        public bool CtrlKey { get; set; }
++        public long Detail { get; set; }
++        public bool MetaKey { get; set; }
++        public bool ShiftKey { get; set; }
++        public TouchPoint[] TargetTouches { get; set; }
++        public TouchPoint[] Touches { get; set; }
++        public string Type { get; set; }
++    }
++    public class TouchPoint {
++        public TouchPoint();
++        public double ClientX { get; set; }
++        public double ClientY { get; set; }
++        public long Identifier { get; set; }
++        public double PageX { get; set; }
++        public double PageY { get; set; }
++        public double ScreenX { get; set; }
++        public double ScreenY { get; set; }
++    }
++    public static class WebEventCallbackFactoryEventArgsExtensions {
++        public static EventCallback<ClipboardEventArgs> Create(this EventCallbackFactory factory, object receiver, Action<ClipboardEventArgs> callback);
++        public static EventCallback<DragEventArgs> Create(this EventCallbackFactory factory, object receiver, Action<DragEventArgs> callback);
++        public static EventCallback<ErrorEventArgs> Create(this EventCallbackFactory factory, object receiver, Action<ErrorEventArgs> callback);
++        public static EventCallback<FocusEventArgs> Create(this EventCallbackFactory factory, object receiver, Action<FocusEventArgs> callback);
++        public static EventCallback<KeyboardEventArgs> Create(this EventCallbackFactory factory, object receiver, Action<KeyboardEventArgs> callback);
++        public static EventCallback<MouseEventArgs> Create(this EventCallbackFactory factory, object receiver, Action<MouseEventArgs> callback);
++        public static EventCallback<PointerEventArgs> Create(this EventCallbackFactory factory, object receiver, Action<PointerEventArgs> callback);
++        public static EventCallback<ProgressEventArgs> Create(this EventCallbackFactory factory, object receiver, Action<ProgressEventArgs> callback);
++        public static EventCallback<TouchEventArgs> Create(this EventCallbackFactory factory, object receiver, Action<TouchEventArgs> callback);
++        public static EventCallback<WheelEventArgs> Create(this EventCallbackFactory factory, object receiver, Action<WheelEventArgs> callback);
++        public static EventCallback<ClipboardEventArgs> Create(this EventCallbackFactory factory, object receiver, Func<ClipboardEventArgs, Task> callback);
++        public static EventCallback<DragEventArgs> Create(this EventCallbackFactory factory, object receiver, Func<DragEventArgs, Task> callback);
++        public static EventCallback<ErrorEventArgs> Create(this EventCallbackFactory factory, object receiver, Func<ErrorEventArgs, Task> callback);
++        public static EventCallback<FocusEventArgs> Create(this EventCallbackFactory factory, object receiver, Func<FocusEventArgs, Task> callback);
++        public static EventCallback<KeyboardEventArgs> Create(this EventCallbackFactory factory, object receiver, Func<KeyboardEventArgs, Task> callback);
++        public static EventCallback<MouseEventArgs> Create(this EventCallbackFactory factory, object receiver, Func<MouseEventArgs, Task> callback);
++        public static EventCallback<PointerEventArgs> Create(this EventCallbackFactory factory, object receiver, Func<PointerEventArgs, Task> callback);
++        public static EventCallback<ProgressEventArgs> Create(this EventCallbackFactory factory, object receiver, Func<ProgressEventArgs, Task> callback);
++        public static EventCallback<TouchEventArgs> Create(this EventCallbackFactory factory, object receiver, Func<TouchEventArgs, Task> callback);
++        public static EventCallback<WheelEventArgs> Create(this EventCallbackFactory factory, object receiver, Func<WheelEventArgs, Task> callback);
++    }
++    public class WheelEventArgs : MouseEventArgs {
++        public WheelEventArgs();
++        public long DeltaMode { get; set; }
++        public double DeltaX { get; set; }
++        public double DeltaY { get; set; }
++        public double DeltaZ { get; set; }
++    }
+ }
+```
+
diff --git a/release-notes/3.0/preview/api-diff/preview9/Asp.Net/3.0-preview9_Microsoft.AspNetCore.Components.md b/release-notes/3.0/preview/api-diff/preview9/Asp.Net/3.0-preview9_Microsoft.AspNetCore.Components.md
new file mode 100644
index 00000000..2dc92848
--- /dev/null
+++ b/release-notes/3.0/preview/api-diff/preview9/Asp.Net/3.0-preview9_Microsoft.AspNetCore.Components.md
@@ -0,0 +1,639 @@
+# Microsoft.AspNetCore.Components
+
+``` diff
+ namespace Microsoft.AspNetCore.Components {
+-    public class AuthenticationState {
+ {
+-        public AuthenticationState(ClaimsPrincipal user);
+
+-        public ClaimsPrincipal User { get; }
+
+-    }
+-    public delegate void AuthenticationStateChangedHandler(Task<AuthenticationState> task);
+
+-    public abstract class AuthenticationStateProvider {
+ {
+-        protected AuthenticationStateProvider();
+
+-        public event AuthenticationStateChangedHandler AuthenticationStateChanged;
+
+-        public abstract Task<AuthenticationState> GetAuthenticationStateAsync();
+
+-        protected void NotifyAuthenticationStateChanged(Task<AuthenticationState> task);
+
+-    }
+-    public class AuthorizeView : AuthorizeViewCore {
+ {
+-        public AuthorizeView();
+
+-        public string Policy { get; set; }
+
+-        public string Roles { get; set; }
+
+-        protected override IAuthorizeData[] GetAuthorizeData();
+
+-    }
+-    public abstract class AuthorizeViewCore : ComponentBase {
+ {
+-        protected AuthorizeViewCore();
+
+-        public RenderFragment<AuthenticationState> Authorized { get; set; }
+
+-        public RenderFragment Authorizing { get; set; }
+
+-        public RenderFragment<AuthenticationState> ChildContent { get; set; }
+
+-        public RenderFragment<AuthenticationState> NotAuthorized { get; set; }
+
+-        public object Resource { get; set; }
+
+-        protected override void BuildRenderTree(RenderTreeBuilder builder);
+
+-        protected abstract IAuthorizeData[] GetAuthorizeData();
+
+-        protected override Task OnParametersSetAsync();
+
+-    }
+-    public static class BindAttributes
+
+     public static class BindConverter {
+         public static string FormatValue(Decimal value, CultureInfo culture = null);
+         public static string FormatValue(Nullable<Decimal> value, CultureInfo culture = null);
+         public static bool TryConvertToDecimal(object obj, CultureInfo culture, out Decimal value);
+         public static bool TryConvertToNullableDecimal(object obj, CultureInfo culture, out Nullable<Decimal> value);
+     }
+-    public class CascadingAuthenticationState : ComponentBase, IDisposable {
+ {
+-        public CascadingAuthenticationState();
+
+-        public RenderFragment ChildContent { get; set; }
+
+-        protected override void BuildRenderTree(RenderTreeBuilder builder);
+
+-        protected override void OnInitialized();
+
+-        void System.IDisposable.Dispose();
+
+-    }
+-    public class CascadingValue<T> : IComponent {
+ {
+-        public CascadingValue();
+
+-        public RenderFragment ChildContent { get; set; }
+
+-        public bool IsFixed { get; set; }
+
+-        public string Name { get; set; }
+
+-        public T Value { get; set; }
+
+-        public void Attach(RenderHandle renderHandle);
+
+-        public Task SetParametersAsync(ParameterView parameters);
+
+-    }
++    public class CascadingValue<TValue> : IComponent {
++        public CascadingValue();
++        public RenderFragment ChildContent { get; set; }
++        public bool IsFixed { get; set; }
++        public string Name { get; set; }
++        public TValue Value { get; set; }
++        public void Attach(RenderHandle renderHandle);
++        public Task SetParametersAsync(ParameterView parameters);
++    }
++    public class ChangeEventArgs : EventArgs {
++        public ChangeEventArgs();
++        public object Value { get; set; }
++    }
+     public abstract class ComponentBase : IComponent, IHandleAfterRender, IHandleEvent {
++        protected virtual void BuildRenderTree(RenderTreeBuilder builder);
+-        protected virtual void BuildRenderTree(RenderTreeBuilder builder);
+
+-        protected virtual void OnAfterRender();
+
++        protected virtual void OnAfterRender(bool firstRender);
+-        protected virtual Task OnAfterRenderAsync();
+
++        protected virtual Task OnAfterRenderAsync(bool firstRender);
+     }
+-    public class DataTransfer {
+ {
+-        public DataTransfer();
+
+-        public string DropEffect { get; set; }
+
+-        public string EffectAllowed { get; set; }
+
+-        public string[] Files { get; set; }
+
+-        public UIDataTransferItem[] Items { get; set; }
+
+-        public string[] Types { get; set; }
+
+-    }
+     public abstract class Dispatcher {
++        public void AssertAccess();
+     }
+     public readonly struct ElementReference {
++        public ElementReference(string id);
++        public string Id { get; }
+     }
+-    public readonly struct EventCallback<T> {
+ {
+-        public static readonly EventCallback<T> Empty;
+
+-        public EventCallback(IHandleEvent receiver, MulticastDelegate @delegate);
+
+-        public bool HasDelegate { get; }
+
+-        public Task InvokeAsync(T arg);
+
+-    }
++    public readonly struct EventCallback<TValue> {
++        public static readonly EventCallback<TValue> Empty;
++        public EventCallback(IHandleEvent receiver, MulticastDelegate @delegate);
++        public bool HasDelegate { get; }
++        public Task InvokeAsync(TValue arg);
++    }
+     public sealed class EventCallbackFactory {
+-        public EventCallback<T> Create<T>(object receiver, EventCallback callback);
+
+-        public EventCallback<T> Create<T>(object receiver, EventCallback<T> callback);
+
+-        public EventCallback<T> Create<T>(object receiver, Action callback);
+
+-        public EventCallback<T> Create<T>(object receiver, Action<T> callback);
+
+-        public EventCallback<T> Create<T>(object receiver, Func<Task> callback);
+
+-        public EventCallback<T> Create<T>(object receiver, Func<T, Task> callback);
+
++        public EventCallback<TValue> Create<TValue>(object receiver, EventCallback callback);
++        public EventCallback<TValue> Create<TValue>(object receiver, EventCallback<TValue> callback);
++        public EventCallback<TValue> Create<TValue>(object receiver, Action callback);
++        public EventCallback<TValue> Create<TValue>(object receiver, Action<TValue> callback);
++        public EventCallback<TValue> Create<TValue>(object receiver, Func<Task> callback);
++        public EventCallback<TValue> Create<TValue>(object receiver, Func<TValue, Task> callback);
+-        public EventCallback<T> CreateInferred<T>(object receiver, Action<T> callback, T value);
+
+-        public EventCallback<T> CreateInferred<T>(object receiver, Func<T, Task> callback, T value);
+
++        public EventCallback<TValue> CreateInferred<TValue>(object receiver, Action<TValue> callback, TValue value);
++        public EventCallback<TValue> CreateInferred<TValue>(object receiver, Func<TValue, Task> callback, TValue value);
+     }
+     public static class EventCallbackFactoryBinderExtensions {
+-        public static EventCallback<UIChangeEventArgs> CreateBinder(this EventCallbackFactory factory, object receiver, Action<bool> setter, bool existingValue, CultureInfo culture = null);
+
++        public static EventCallback<ChangeEventArgs> CreateBinder(this EventCallbackFactory factory, object receiver, Action<bool> setter, bool existingValue, CultureInfo culture = null);
+-        public static EventCallback<UIChangeEventArgs> CreateBinder(this EventCallbackFactory factory, object receiver, Action<DateTime> setter, DateTime existingValue, CultureInfo culture = null);
+
++        public static EventCallback<ChangeEventArgs> CreateBinder(this EventCallbackFactory factory, object receiver, Action<DateTime> setter, DateTime existingValue, CultureInfo culture = null);
+-        public static EventCallback<UIChangeEventArgs> CreateBinder(this EventCallbackFactory factory, object receiver, Action<DateTime> setter, DateTime existingValue, string format, CultureInfo culture = null);
+
++        public static EventCallback<ChangeEventArgs> CreateBinder(this EventCallbackFactory factory, object receiver, Action<DateTime> setter, DateTime existingValue, string format, CultureInfo culture = null);
+-        public static EventCallback<UIChangeEventArgs> CreateBinder(this EventCallbackFactory factory, object receiver, Action<DateTimeOffset> setter, DateTimeOffset existingValue, CultureInfo culture = null);
+
++        public static EventCallback<ChangeEventArgs> CreateBinder(this EventCallbackFactory factory, object receiver, Action<DateTimeOffset> setter, DateTimeOffset existingValue, CultureInfo culture = null);
+-        public static EventCallback<UIChangeEventArgs> CreateBinder(this EventCallbackFactory factory, object receiver, Action<DateTimeOffset> setter, DateTimeOffset existingValue, string format, CultureInfo culture = null);
+
++        public static EventCallback<ChangeEventArgs> CreateBinder(this EventCallbackFactory factory, object receiver, Action<DateTimeOffset> setter, DateTimeOffset existingValue, string format, CultureInfo culture = null);
+-        public static EventCallback<UIChangeEventArgs> CreateBinder(this EventCallbackFactory factory, object receiver, Action<Decimal> setter, Decimal existingValue, CultureInfo culture = null);
+
++        public static EventCallback<ChangeEventArgs> CreateBinder(this EventCallbackFactory factory, object receiver, Action<decimal> setter, decimal existingValue, CultureInfo culture = null);
+-        public static EventCallback<UIChangeEventArgs> CreateBinder(this EventCallbackFactory factory, object receiver, Action<double> setter, double existingValue, CultureInfo culture = null);
+
++        public static EventCallback<ChangeEventArgs> CreateBinder(this EventCallbackFactory factory, object receiver, Action<double> setter, double existingValue, CultureInfo culture = null);
+-        public static EventCallback<UIChangeEventArgs> CreateBinder(this EventCallbackFactory factory, object receiver, Action<int> setter, int existingValue, CultureInfo culture = null);
+
++        public static EventCallback<ChangeEventArgs> CreateBinder(this EventCallbackFactory factory, object receiver, Action<int> setter, int existingValue, CultureInfo culture = null);
+-        public static EventCallback<UIChangeEventArgs> CreateBinder(this EventCallbackFactory factory, object receiver, Action<long> setter, long existingValue, CultureInfo culture = null);
+
++        public static EventCallback<ChangeEventArgs> CreateBinder(this EventCallbackFactory factory, object receiver, Action<long> setter, long existingValue, CultureInfo culture = null);
+-        public static EventCallback<UIChangeEventArgs> CreateBinder(this EventCallbackFactory factory, object receiver, Action<Nullable<bool>> setter, Nullable<bool> existingValue, CultureInfo culture = null);
+
++        public static EventCallback<ChangeEventArgs> CreateBinder(this EventCallbackFactory factory, object receiver, Action<Nullable<bool>> setter, Nullable<bool> existingValue, CultureInfo culture = null);
+-        public static EventCallback<UIChangeEventArgs> CreateBinder(this EventCallbackFactory factory, object receiver, Action<Nullable<DateTime>> setter, Nullable<DateTime> existingValue, CultureInfo culture = null);
+
++        public static EventCallback<ChangeEventArgs> CreateBinder(this EventCallbackFactory factory, object receiver, Action<Nullable<DateTime>> setter, Nullable<DateTime> existingValue, CultureInfo culture = null);
+-        public static EventCallback<UIChangeEventArgs> CreateBinder(this EventCallbackFactory factory, object receiver, Action<Nullable<DateTime>> setter, Nullable<DateTime> existingValue, string format, CultureInfo culture = null);
+
++        public static EventCallback<ChangeEventArgs> CreateBinder(this EventCallbackFactory factory, object receiver, Action<Nullable<DateTime>> setter, Nullable<DateTime> existingValue, string format, CultureInfo culture = null);
+-        public static EventCallback<UIChangeEventArgs> CreateBinder(this EventCallbackFactory factory, object receiver, Action<Nullable<DateTimeOffset>> setter, Nullable<DateTimeOffset> existingValue, CultureInfo culture = null);
+
++        public static EventCallback<ChangeEventArgs> CreateBinder(this EventCallbackFactory factory, object receiver, Action<Nullable<DateTimeOffset>> setter, Nullable<DateTimeOffset> existingValue, CultureInfo culture = null);
+-        public static EventCallback<UIChangeEventArgs> CreateBinder(this EventCallbackFactory factory, object receiver, Action<Nullable<DateTimeOffset>> setter, Nullable<DateTimeOffset> existingValue, string format, CultureInfo culture = null);
+
++        public static EventCallback<ChangeEventArgs> CreateBinder(this EventCallbackFactory factory, object receiver, Action<Nullable<DateTimeOffset>> setter, Nullable<DateTimeOffset> existingValue, string format, CultureInfo culture = null);
+-        public static EventCallback<UIChangeEventArgs> CreateBinder(this EventCallbackFactory factory, object receiver, Action<Nullable<Decimal>> setter, Nullable<Decimal> existingValue, CultureInfo culture = null);
+
++        public static EventCallback<ChangeEventArgs> CreateBinder(this EventCallbackFactory factory, object receiver, Action<Nullable<decimal>> setter, Nullable<decimal> existingValue, CultureInfo culture = null);
+-        public static EventCallback<UIChangeEventArgs> CreateBinder(this EventCallbackFactory factory, object receiver, Action<Nullable<double>> setter, Nullable<double> existingValue, CultureInfo culture = null);
+
++        public static EventCallback<ChangeEventArgs> CreateBinder(this EventCallbackFactory factory, object receiver, Action<Nullable<double>> setter, Nullable<double> existingValue, CultureInfo culture = null);
+-        public static EventCallback<UIChangeEventArgs> CreateBinder(this EventCallbackFactory factory, object receiver, Action<Nullable<int>> setter, Nullable<int> existingValue, CultureInfo culture = null);
+
++        public static EventCallback<ChangeEventArgs> CreateBinder(this EventCallbackFactory factory, object receiver, Action<Nullable<int>> setter, Nullable<int> existingValue, CultureInfo culture = null);
+-        public static EventCallback<UIChangeEventArgs> CreateBinder(this EventCallbackFactory factory, object receiver, Action<Nullable<long>> setter, Nullable<long> existingValue, CultureInfo culture = null);
+
++        public static EventCallback<ChangeEventArgs> CreateBinder(this EventCallbackFactory factory, object receiver, Action<Nullable<long>> setter, Nullable<long> existingValue, CultureInfo culture = null);
+-        public static EventCallback<UIChangeEventArgs> CreateBinder(this EventCallbackFactory factory, object receiver, Action<Nullable<float>> setter, Nullable<float> existingValue, CultureInfo culture = null);
+
++        public static EventCallback<ChangeEventArgs> CreateBinder(this EventCallbackFactory factory, object receiver, Action<Nullable<float>> setter, Nullable<float> existingValue, CultureInfo culture = null);
+-        public static EventCallback<UIChangeEventArgs> CreateBinder(this EventCallbackFactory factory, object receiver, Action<float> setter, float existingValue, CultureInfo culture = null);
+
++        public static EventCallback<ChangeEventArgs> CreateBinder(this EventCallbackFactory factory, object receiver, Action<float> setter, float existingValue, CultureInfo culture = null);
+-        public static EventCallback<UIChangeEventArgs> CreateBinder(this EventCallbackFactory factory, object receiver, Action<string> setter, string existingValue, CultureInfo culture = null);
+
++        public static EventCallback<ChangeEventArgs> CreateBinder(this EventCallbackFactory factory, object receiver, Action<string> setter, string existingValue, CultureInfo culture = null);
+-        public static EventCallback<UIChangeEventArgs> CreateBinder<T>(this EventCallbackFactory factory, object receiver, Action<T> setter, T existingValue, CultureInfo culture = null);
+
++        public static EventCallback<ChangeEventArgs> CreateBinder<T>(this EventCallbackFactory factory, object receiver, Action<T> setter, T existingValue, CultureInfo culture = null);
+     }
++    public static class EventCallbackFactoryEventArgsExtensions {
++        public static EventCallback<ChangeEventArgs> Create(this EventCallbackFactory factory, object receiver, Action<ChangeEventArgs> callback);
++        public static EventCallback<EventArgs> Create(this EventCallbackFactory factory, object receiver, Action<EventArgs> callback);
++        public static EventCallback<ChangeEventArgs> Create(this EventCallbackFactory factory, object receiver, Func<ChangeEventArgs, Task> callback);
++        public static EventCallback<EventArgs> Create(this EventCallbackFactory factory, object receiver, Func<EventArgs, Task> callback);
++    }
+-    public static class EventCallbackFactoryUIEventArgsExtensions {
+ {
+-        public static EventCallback<UIChangeEventArgs> Create(this EventCallbackFactory factory, object receiver, Action<UIChangeEventArgs> callback);
+
+-        public static EventCallback<UIEventArgs> Create(this EventCallbackFactory factory, object receiver, Action<UIEventArgs> callback);
+
+-        public static EventCallback<UIChangeEventArgs> Create(this EventCallbackFactory factory, object receiver, Func<UIChangeEventArgs, Task> callback);
+
+-        public static EventCallback<UIEventArgs> Create(this EventCallbackFactory factory, object receiver, Func<UIEventArgs, Task> callback);
+
+-    }
+-    public static class EventHandlers
+
+-    public interface IComponentContext {
+ {
+-        bool IsConnected { get; }
+
+-    }
+-    public interface IHostEnvironmentAuthenticationStateProvider {
+ {
+-        void SetAuthenticationState(Task<AuthenticationState> authenticationStateTask);
+
+-    }
+-    public interface IUriHelper {
+ {
+-        event EventHandler<LocationChangedEventArgs> OnLocationChanged;
+
+-        string GetAbsoluteUri();
+
+-        string GetBaseUri();
+
+-        void NavigateTo(string uri);
+
+-        void NavigateTo(string uri, bool forceLoad);
+
+-        Uri ToAbsoluteUri(string href);
+
+-        string ToBaseRelativePath(string baseUri, string locationAbsolute);
+
+-    }
++    public class LayoutView : IComponent {
++        public LayoutView();
++        public RenderFragment ChildContent { get; set; }
++        public Type Layout { get; set; }
++        public void Attach(RenderHandle renderHandle);
++        public Task SetParametersAsync(ParameterView parameters);
++    }
++    public sealed class LocationChangeException : Exception {
++        public LocationChangeException(string message, Exception innerException);
++    }
++    public abstract class NavigationManager {
++        protected NavigationManager();
++        public string BaseUri { get; protected set; }
++        public string Uri { get; protected set; }
++        public event EventHandler<LocationChangedEventArgs> LocationChanged;
++        protected virtual void EnsureInitialized();
++        protected void Initialize(string baseUri, string uri);
++        public void NavigateTo(string uri, bool forceLoad = false);
++        protected abstract void NavigateToCore(string uri, bool forceLoad);
++        protected void NotifyLocationChanged(bool isInterceptedLink);
++        public Uri ToAbsoluteUri(string relativeUri);
++        public string ToBaseRelativePath(string uri);
++    }
++    public abstract class OwningComponentBase : ComponentBase, IDisposable {
++        protected OwningComponentBase();
++        protected bool IsDisposed { get; }
++        protected IServiceProvider ScopedServices { get; }
++        protected virtual void Dispose(bool disposing);
++        void System.IDisposable.Dispose();
++    }
++    public abstract class OwningComponentBase<TService> : OwningComponentBase, IDisposable {
++        protected OwningComponentBase();
++        protected TService Service { get; }
++    }
+-    public class PageDisplay : IComponent {
+ {
+-        public PageDisplay();
+
+-        public RenderFragment AuthorizingContent { get; set; }
+
+-        public RenderFragment<AuthenticationState> NotAuthorizedContent { get; set; }
+
+-        public Type Page { get; set; }
+
+-        public IDictionary<string, object> PageParameters { get; set; }
+
+-        public void Attach(RenderHandle renderHandle);
+
+-        public Task SetParametersAsync(ParameterView parameters);
+
+-    }
+     public readonly struct ParameterView {
+-        public T GetValueOrDefault<T>(string parameterName);
+
+-        public T GetValueOrDefault<T>(string parameterName, T defaultValue);
+
++        public TValue GetValueOrDefault<TValue>(string parameterName);
++        public TValue GetValueOrDefault<TValue>(string parameterName, TValue defaultValue);
+-        public bool TryGetValue<T>(string parameterName, out T result);
+
++        public bool TryGetValue<TValue>(string parameterName, out TValue result);
+     }
+     public delegate void RenderFragment(RenderTreeBuilder builder);
+-    public delegate RenderFragment RenderFragment<T>(T value);
+
++    public delegate RenderFragment RenderFragment<TValue>(TValue value);
++    public sealed class RouteData {
++        public RouteData(Type pageType, IReadOnlyDictionary<string, object> routeValues);
++        public Type PageType { get; }
++        public IReadOnlyDictionary<string, object> RouteValues { get; }
++    }
++    public class RouteView : IComponent {
++        public RouteView();
++        public Type DefaultLayout { get; set; }
++        public RouteData RouteData { get; set; }
++        public void Attach(RenderHandle renderHandle);
++        protected virtual void Render(RenderTreeBuilder builder);
++        public Task SetParametersAsync(ParameterView parameters);
++    }
+-    public class UIChangeEventArgs : UIEventArgs {
+ {
+-        public UIChangeEventArgs();
+
+-        public object Value { get; set; }
+
+-    }
+-    public class UIClipboardEventArgs : UIEventArgs {
+ {
+-        public UIClipboardEventArgs();
+
+-    }
+-    public class UIDataTransferItem {
+ {
+-        public UIDataTransferItem();
+
+-        public string Kind { get; set; }
+
+-        public string Type { get; set; }
+
+-    }
+-    public class UIDragEventArgs : UIMouseEventArgs {
+ {
+-        public UIDragEventArgs();
+
+-        public DataTransfer DataTransfer { get; set; }
+
+-    }
+-    public class UIErrorEventArgs : UIEventArgs {
+ {
+-        public UIErrorEventArgs();
+
+-        public int Colno { get; set; }
+
+-        public string Filename { get; set; }
+
+-        public int Lineno { get; set; }
+
+-        public string Message { get; set; }
+
+-    }
+-    public class UIEventArgs {
+ {
+-        public UIEventArgs();
+
+-        public string Type { get; set; }
+
+-    }
+-    public class UIFocusEventArgs : UIEventArgs {
+ {
+-        public UIFocusEventArgs();
+
+-    }
+-    public class UIKeyboardEventArgs : UIEventArgs {
+ {
+-        public UIKeyboardEventArgs();
+
+-        public bool AltKey { get; set; }
+
+-        public string Code { get; set; }
+
+-        public bool CtrlKey { get; set; }
+
+-        public string Key { get; set; }
+
+-        public float Location { get; set; }
+
+-        public bool MetaKey { get; set; }
+
+-        public bool Repeat { get; set; }
+
+-        public bool ShiftKey { get; set; }
+
+-    }
+-    public class UIMouseEventArgs : UIEventArgs {
+ {
+-        public UIMouseEventArgs();
+
+-        public bool AltKey { get; set; }
+
+-        public long Button { get; set; }
+
+-        public long Buttons { get; set; }
+
+-        public double ClientX { get; set; }
+
+-        public double ClientY { get; set; }
+
+-        public bool CtrlKey { get; set; }
+
+-        public long Detail { get; set; }
+
+-        public bool MetaKey { get; set; }
+
+-        public double ScreenX { get; set; }
+
+-        public double ScreenY { get; set; }
+
+-        public bool ShiftKey { get; set; }
+
+-    }
+-    public class UIPointerEventArgs : UIMouseEventArgs {
+ {
+-        public UIPointerEventArgs();
+
+-        public float Height { get; set; }
+
+-        public bool IsPrimary { get; set; }
+
+-        public long PointerId { get; set; }
+
+-        public string PointerType { get; set; }
+
+-        public float Pressure { get; set; }
+
+-        public float TiltX { get; set; }
+
+-        public float TiltY { get; set; }
+
+-        public float Width { get; set; }
+
+-    }
+-    public class UIProgressEventArgs : UIEventArgs {
+ {
+-        public UIProgressEventArgs();
+
+-        public bool LengthComputable { get; set; }
+
+-        public long Loaded { get; set; }
+
+-        public long Total { get; set; }
+
+-    }
+-    public class UITouchEventArgs : UIEventArgs {
+ {
+-        public UITouchEventArgs();
+
+-        public bool AltKey { get; set; }
+
+-        public UITouchPoint[] ChangedTouches { get; set; }
+
+-        public bool CtrlKey { get; set; }
+
+-        public long Detail { get; set; }
+
+-        public bool MetaKey { get; set; }
+
+-        public bool ShiftKey { get; set; }
+
+-        public UITouchPoint[] TargetTouches { get; set; }
+
+-        public UITouchPoint[] Touches { get; set; }
+
+-    }
+-    public class UITouchPoint {
+ {
+-        public UITouchPoint();
+
+-        public double ClientX { get; set; }
+
+-        public double ClientY { get; set; }
+
+-        public long Identifier { get; set; }
+
+-        public double PageX { get; set; }
+
+-        public double PageY { get; set; }
+
+-        public double ScreenX { get; set; }
+
+-        public double ScreenY { get; set; }
+
+-    }
+-    public class UIWheelEventArgs : UIMouseEventArgs {
+ {
+-        public UIWheelEventArgs();
+
+-        public long DeltaMode { get; set; }
+
+-        public double DeltaX { get; set; }
+
+-        public double DeltaY { get; set; }
+
+-        public double DeltaZ { get; set; }
+
+-    }
+-    public abstract class UriHelperBase : IUriHelper {
+ {
+-        protected UriHelperBase();
+
+-        public event EventHandler<LocationChangedEventArgs> OnLocationChanged;
+
+-        protected virtual void EnsureInitialized();
+
+-        public string GetAbsoluteUri();
+
+-        public virtual string GetBaseUri();
+
+-        public virtual void InitializeState(string uriAbsolute, string baseUriAbsolute);
+
+-        public void NavigateTo(string uri);
+
+-        public void NavigateTo(string uri, bool forceLoad);
+
+-        protected abstract void NavigateToCore(string uri, bool forceLoad);
+
+-        protected void SetAbsoluteBaseUri(string baseUri);
+
+-        protected void SetAbsoluteUri(string uri);
+
+-        public Uri ToAbsoluteUri(string href);
+
+-        public string ToBaseRelativePath(string baseUri, string locationAbsolute);
+
+-        protected void TriggerOnLocationChanged(bool isinterceptedLink);
+
+-    }
+-    public static class WebEventCallbackFactoryUIEventArgsExtensions {
+ {
+-        public static EventCallback<UIClipboardEventArgs> Create(this EventCallbackFactory factory, object receiver, Action<UIClipboardEventArgs> callback);
+
+-        public static EventCallback<UIDragEventArgs> Create(this EventCallbackFactory factory, object receiver, Action<UIDragEventArgs> callback);
+
+-        public static EventCallback<UIErrorEventArgs> Create(this EventCallbackFactory factory, object receiver, Action<UIErrorEventArgs> callback);
+
+-        public static EventCallback<UIFocusEventArgs> Create(this EventCallbackFactory factory, object receiver, Action<UIFocusEventArgs> callback);
+
+-        public static EventCallback<UIKeyboardEventArgs> Create(this EventCallbackFactory factory, object receiver, Action<UIKeyboardEventArgs> callback);
+
+-        public static EventCallback<UIMouseEventArgs> Create(this EventCallbackFactory factory, object receiver, Action<UIMouseEventArgs> callback);
+
+-        public static EventCallback<UIPointerEventArgs> Create(this EventCallbackFactory factory, object receiver, Action<UIPointerEventArgs> callback);
+
+-        public static EventCallback<UIProgressEventArgs> Create(this EventCallbackFactory factory, object receiver, Action<UIProgressEventArgs> callback);
+
+-        public static EventCallback<UITouchEventArgs> Create(this EventCallbackFactory factory, object receiver, Action<UITouchEventArgs> callback);
+
+-        public static EventCallback<UIWheelEventArgs> Create(this EventCallbackFactory factory, object receiver, Action<UIWheelEventArgs> callback);
+
+-        public static EventCallback<UIClipboardEventArgs> Create(this EventCallbackFactory factory, object receiver, Func<UIClipboardEventArgs, Task> callback);
+
+-        public static EventCallback<UIDragEventArgs> Create(this EventCallbackFactory factory, object receiver, Func<UIDragEventArgs, Task> callback);
+
+-        public static EventCallback<UIErrorEventArgs> Create(this EventCallbackFactory factory, object receiver, Func<UIErrorEventArgs, Task> callback);
+
+-        public static EventCallback<UIFocusEventArgs> Create(this EventCallbackFactory factory, object receiver, Func<UIFocusEventArgs, Task> callback);
+
+-        public static EventCallback<UIKeyboardEventArgs> Create(this EventCallbackFactory factory, object receiver, Func<UIKeyboardEventArgs, Task> callback);
+
+-        public static EventCallback<UIMouseEventArgs> Create(this EventCallbackFactory factory, object receiver, Func<UIMouseEventArgs, Task> callback);
+
+-        public static EventCallback<UIPointerEventArgs> Create(this EventCallbackFactory factory, object receiver, Func<UIPointerEventArgs, Task> callback);
+
+-        public static EventCallback<UIProgressEventArgs> Create(this EventCallbackFactory factory, object receiver, Func<UIProgressEventArgs, Task> callback);
+
+-        public static EventCallback<UITouchEventArgs> Create(this EventCallbackFactory factory, object receiver, Func<UITouchEventArgs, Task> callback);
+
+-        public static EventCallback<UIWheelEventArgs> Create(this EventCallbackFactory factory, object receiver, Func<UIWheelEventArgs, Task> callback);
+
+-    }
+ }
+```
+
diff --git a/release-notes/3.0/preview/api-diff/preview9/Asp.Net/3.0-preview9_Microsoft.AspNetCore.Mvc.Formatters.md b/release-notes/3.0/preview/api-diff/preview9/Asp.Net/3.0-preview9_Microsoft.AspNetCore.Mvc.Formatters.md
new file mode 100644
index 00000000..73a4d0ec
--- /dev/null
+++ b/release-notes/3.0/preview/api-diff/preview9/Asp.Net/3.0-preview9_Microsoft.AspNetCore.Mvc.Formatters.md
@@ -0,0 +1,12 @@
+# Microsoft.AspNetCore.Mvc.Formatters
+
+``` diff
+ namespace Microsoft.AspNetCore.Mvc.Formatters {
+     public class SystemTextJsonOutputFormatter : TextOutputFormatter {
+-        public SystemTextJsonOutputFormatter(JsonOptions options);
+
++        public SystemTextJsonOutputFormatter(JsonSerializerOptions jsonSerializerOptions);
+     }
+ }
+```
+
diff --git a/release-notes/3.0/preview/api-diff/preview9/Asp.Net/3.0-preview9_Microsoft.AspNetCore.Mvc.Infrastructure.md b/release-notes/3.0/preview/api-diff/preview9/Asp.Net/3.0-preview9_Microsoft.AspNetCore.Mvc.Infrastructure.md
new file mode 100644
index 00000000..da5c1cf5
--- /dev/null
+++ b/release-notes/3.0/preview/api-diff/preview9/Asp.Net/3.0-preview9_Microsoft.AspNetCore.Mvc.Infrastructure.md
@@ -0,0 +1,12 @@
+# Microsoft.AspNetCore.Mvc.Infrastructure
+
+``` diff
+ namespace Microsoft.AspNetCore.Mvc.Infrastructure {
++    public abstract class ProblemDetailsFactory {
++        protected ProblemDetailsFactory();
++        public abstract ProblemDetails CreateProblemDetails(HttpContext httpContext, Nullable<int> statusCode = default(Nullable<int>), string title = null, string type = null, string detail = null, string instance = null);
++        public abstract ValidationProblemDetails CreateValidationProblemDetails(HttpContext httpContext, ModelStateDictionary modelStateDictionary, Nullable<int> statusCode = default(Nullable<int>), string title = null, string type = null, string detail = null, string instance = null);
++    }
+ }
+```
+
diff --git a/release-notes/3.0/preview/api-diff/preview9/Asp.Net/3.0-preview9_Microsoft.AspNetCore.Mvc.ModelBinding.md b/release-notes/3.0/preview/api-diff/preview9/Asp.Net/3.0-preview9_Microsoft.AspNetCore.Mvc.ModelBinding.md
new file mode 100644
index 00000000..607050dd
--- /dev/null
+++ b/release-notes/3.0/preview/api-diff/preview9/Asp.Net/3.0-preview9_Microsoft.AspNetCore.Mvc.ModelBinding.md
@@ -0,0 +1,16 @@
+# Microsoft.AspNetCore.Mvc.ModelBinding
+
+``` diff
+ namespace Microsoft.AspNetCore.Mvc.ModelBinding {
++    public sealed class FormFileValueProvider : IValueProvider {
++        public FormFileValueProvider(IFormFileCollection files);
++        public bool ContainsPrefix(string prefix);
++        public ValueProviderResult GetValue(string key);
++    }
++    public sealed class FormFileValueProviderFactory : IValueProviderFactory {
++        public FormFileValueProviderFactory();
++        public Task CreateValueProviderAsync(ValueProviderFactoryContext context);
++    }
+ }
+```
+
diff --git a/release-notes/3.0/preview/api-diff/preview9/Asp.Net/3.0-preview9_Microsoft.AspNetCore.Mvc.RazorPages.md b/release-notes/3.0/preview/api-diff/preview9/Asp.Net/3.0-preview9_Microsoft.AspNetCore.Mvc.RazorPages.md
new file mode 100644
index 00000000..f3d77c25
--- /dev/null
+++ b/release-notes/3.0/preview/api-diff/preview9/Asp.Net/3.0-preview9_Microsoft.AspNetCore.Mvc.RazorPages.md
@@ -0,0 +1,13 @@
+# Microsoft.AspNetCore.Mvc.RazorPages
+
+``` diff
+ namespace Microsoft.AspNetCore.Mvc.RazorPages {
+     public abstract class PageBase : RazorPageBase {
++        public IModelMetadataProvider MetadataProvider { get; set; }
+     }
+     public abstract class PageModel : IAsyncPageFilter, IFilterMetadata, IPageFilter {
++        public IModelMetadataProvider MetadataProvider { get; set; }
+     }
+ }
+```
+
diff --git a/release-notes/3.0/preview/api-diff/preview9/Asp.Net/3.0-preview9_Microsoft.AspNetCore.Mvc.Rendering.md b/release-notes/3.0/preview/api-diff/preview9/Asp.Net/3.0-preview9_Microsoft.AspNetCore.Mvc.Rendering.md
new file mode 100644
index 00000000..7435f01c
--- /dev/null
+++ b/release-notes/3.0/preview/api-diff/preview9/Asp.Net/3.0-preview9_Microsoft.AspNetCore.Mvc.Rendering.md
@@ -0,0 +1,30 @@
+# Microsoft.AspNetCore.Mvc.Rendering
+
+``` diff
+ namespace Microsoft.AspNetCore.Mvc.Rendering {
++    public static class HtmlHelperComponentExtensions {
++        public static Task<IHtmlContent> RenderComponentAsync<TComponent>(this IHtmlHelper htmlHelper, RenderMode renderMode) where TComponent : IComponent;
++        public static Task<IHtmlContent> RenderComponentAsync<TComponent>(this IHtmlHelper htmlHelper, RenderMode renderMode, object parameters) where TComponent : IComponent;
++    }
+-    public static class HtmlHelperComponentPrerenderingExtensions {
+ {
+-        public static Task<IHtmlContent> RenderComponentAsync<TComponent>(this IHtmlHelper htmlHelper) where TComponent : IComponent;
+
+-        public static Task<IHtmlContent> RenderComponentAsync<TComponent>(this IHtmlHelper htmlHelper, object parameters) where TComponent : IComponent;
+
+-    }
+-    public static class HtmlHelperRazorComponentExtensions {
+ {
+-        public static Task<IHtmlContent> RenderStaticComponentAsync<TComponent>(this IHtmlHelper htmlHelper) where TComponent : IComponent;
+
+-        public static Task<IHtmlContent> RenderStaticComponentAsync<TComponent>(this IHtmlHelper htmlHelper, object parameters) where TComponent : IComponent;
+
+-    }
++    public enum RenderMode {
++        Server = 2,
++        ServerPrerendered = 3,
++        Static = 1,
++    }
+ }
+```
+
diff --git a/release-notes/3.0/preview/api-diff/preview9/Asp.Net/3.0-preview9_Microsoft.AspNetCore.Mvc.md b/release-notes/3.0/preview/api-diff/preview9/Asp.Net/3.0-preview9_Microsoft.AspNetCore.Mvc.md
new file mode 100644
index 00000000..668c95d9
--- /dev/null
+++ b/release-notes/3.0/preview/api-diff/preview9/Asp.Net/3.0-preview9_Microsoft.AspNetCore.Mvc.md
@@ -0,0 +1,12 @@
+# Microsoft.AspNetCore.Mvc
+
+``` diff
+ namespace Microsoft.AspNetCore.Mvc {
+     public abstract class ControllerBase {
++        public ProblemDetailsFactory ProblemDetailsFactory { get; set; }
++        public virtual ObjectResult Problem(string detail = null, string instance = null, Nullable<int> statusCode = default(Nullable<int>), string title = null, string type = null);
++        public virtual ActionResult ValidationProblem(string detail = null, string instance = null, Nullable<int> statusCode = default(Nullable<int>), string title = null, string type = null, ModelStateDictionary modelStateDictionary = null);
+     }
+ }
+```
+
diff --git a/release-notes/3.0/preview/api-diff/preview9/Asp.Net/3.0-preview9_Microsoft.JSInterop.Infrastructure.md b/release-notes/3.0/preview/api-diff/preview9/Asp.Net/3.0-preview9_Microsoft.JSInterop.Infrastructure.md
new file mode 100644
index 00000000..8bd56538
--- /dev/null
+++ b/release-notes/3.0/preview/api-diff/preview9/Asp.Net/3.0-preview9_Microsoft.JSInterop.Infrastructure.md
@@ -0,0 +1,27 @@
+# Microsoft.JSInterop.Infrastructure
+
+``` diff
++namespace Microsoft.JSInterop.Infrastructure {
++    public static class DotNetDispatcher {
++        public static void BeginInvokeDotNet(JSRuntime jsRuntime, DotNetInvocationInfo invocationInfo, string argsJson);
++        public static void EndInvokeJS(JSRuntime jsRuntime, string arguments);
++        public static string Invoke(JSRuntime jsRuntime, in DotNetInvocationInfo invocationInfo, string argsJson);
++    }
++    public readonly struct DotNetInvocationInfo {
++        public DotNetInvocationInfo(string assemblyName, string methodIdentifier, long dotNetObjectId, string callId);
++        public string AssemblyName { get; }
++        public string CallId { get; }
++        public long DotNetObjectId { get; }
++        public string MethodIdentifier { get; }
++    }
++    public readonly struct DotNetInvocationResult {
++        public DotNetInvocationResult(Exception exception, string errorKind);
++        public DotNetInvocationResult(object result);
++        public string ErrorKind { get; }
++        public Exception Exception { get; }
++        public object Result { get; }
++        public bool Success { get; }
++    }
++}
+```
+
diff --git a/release-notes/3.0/preview/api-diff/preview9/Asp.Net/3.0-preview9_Microsoft.JSInterop.md b/release-notes/3.0/preview/api-diff/preview9/Asp.Net/3.0-preview9_Microsoft.JSInterop.md
new file mode 100644
index 00000000..344eef23
--- /dev/null
+++ b/release-notes/3.0/preview/api-diff/preview9/Asp.Net/3.0-preview9_Microsoft.JSInterop.md
@@ -0,0 +1,99 @@
+# Microsoft.JSInterop
+
+``` diff
+ namespace Microsoft.JSInterop {
+-    public static class DotNetDispatcher {
+ {
+-        public static void BeginInvoke(string callId, string assemblyName, string methodIdentifier, long dotNetObjectId, string argsJson);
+
+-        public static void EndInvoke(string arguments);
+
+-        public static string Invoke(string assemblyName, string methodIdentifier, long dotNetObjectId, string argsJson);
+
+-        public static void ReleaseDotNetObject(long dotNetObjectId);
+
+-    }
+-    public static class DotNetObjectRef {
+ {
+-        public static DotNetObjectRef<TValue> Create<TValue>(TValue value) where TValue : class;
+
+-    }
+-    public sealed class DotNetObjectRef<TValue> : IDisposable where TValue : class {
+ {
+-        public TValue Value { get; }
+
+-        public void Dispose();
+
+-    }
++    public static class DotNetObjectReference {
++        public static DotNetObjectReference<TValue> Create<TValue>(TValue value) where TValue : class;
++    }
++    public sealed class DotNetObjectReference<TValue> : IDisposable where TValue : class {
++        public TValue Value { get; }
++        public void Dispose();
++    }
+     public interface IJSRuntime {
+-        Task<TValue> InvokeAsync<TValue>(string identifier, IEnumerable<object> args, CancellationToken cancellationToken = default(CancellationToken));
+
+-        Task<TValue> InvokeAsync<TValue>(string identifier, params object[] args);
+
++        ValueTask<TValue> InvokeAsync<TValue>(string identifier, object[] args);
++        ValueTask<TValue> InvokeAsync<TValue>(string identifier, CancellationToken cancellationToken, object[] args);
+     }
++    public abstract class JSInProcessRuntime : JSRuntime, IJSInProcessRuntime, IJSRuntime {
++        protected JSInProcessRuntime();
++        public TValue Invoke<TValue>(string identifier, params object[] args);
++        protected abstract string InvokeJS(string identifier, string argsJson);
++    }
+-    public abstract class JSInProcessRuntimeBase : JSRuntimeBase, IJSInProcessRuntime, IJSRuntime {
+ {
+-        protected JSInProcessRuntimeBase();
+
+-        public TValue Invoke<TValue>(string identifier, params object[] args);
+
+-        protected abstract string InvokeJS(string identifier, string argsJson);
+
+-    }
++    public static class JSInProcessRuntimeExtensions {
++        public static void InvokeVoid(this IJSInProcessRuntime jsRuntime, string identifier, params object[] args);
++    }
+-    public class JSInvokableAttribute : Attribute
++    public sealed class JSInvokableAttribute : Attribute
+-    public static class JSRuntime {
++    public abstract class JSRuntime : IJSRuntime {
++        protected JSRuntime();
++        protected Nullable<TimeSpan> DefaultAsyncTimeout { get; set; }
++        protected internal JsonSerializerOptions JsonSerializerOptions { get; }
++        protected abstract void BeginInvokeJS(long taskId, string identifier, string argsJson);
++        protected internal abstract void EndInvokeDotNet(DotNetInvocationInfo invocationInfo, in DotNetInvocationResult invocationResult);
++        public ValueTask<TValue> InvokeAsync<TValue>(string identifier, object[] args);
++        public ValueTask<TValue> InvokeAsync<TValue>(string identifier, CancellationToken cancellationToken, object[] args);
+-        public static void SetCurrentJSRuntime(IJSRuntime instance);
+
+     }
+-    public abstract class JSRuntimeBase : IJSRuntime {
+ {
+-        protected JSRuntimeBase();
+
+-        protected Nullable<TimeSpan> DefaultAsyncTimeout { get; set; }
+
+-        protected abstract void BeginInvokeJS(long taskId, string identifier, string argsJson);
+
+-        protected internal abstract void EndInvokeDotNet(string callId, bool success, object resultOrError, string assemblyName, string methodIdentifier, long dotNetObjectId);
+
+-        public Task<T> InvokeAsync<T>(string identifier, IEnumerable<object> args, CancellationToken cancellationToken = default(CancellationToken));
+
+-        public Task<T> InvokeAsync<T>(string identifier, params object[] args);
+
+-    }
++    public static class JSRuntimeExtensions {
++        public static ValueTask<TValue> InvokeAsync<TValue>(this IJSRuntime jsRuntime, string identifier, params object[] args);
++        public static ValueTask<TValue> InvokeAsync<TValue>(this IJSRuntime jsRuntime, string identifier, CancellationToken cancellationToken, params object[] args);
++        public static ValueTask<TValue> InvokeAsync<TValue>(this IJSRuntime jsRuntime, string identifier, TimeSpan timeout, params object[] args);
++        public static ValueTask InvokeVoidAsync(this IJSRuntime jsRuntime, string identifier, params object[] args);
++        public static ValueTask InvokeVoidAsync(this IJSRuntime jsRuntime, string identifier, CancellationToken cancellationToken, params object[] args);
++        public static ValueTask InvokeVoidAsync(this IJSRuntime jsRuntime, string identifier, TimeSpan timeout, params object[] args);
++    }
+ }
+```
+
diff --git a/release-notes/3.0/preview/api-diff/preview9/README.md b/release-notes/3.0/preview/api-diff/preview9/README.md
new file mode 100644
index 00000000..f4a9d356
--- /dev/null
+++ b/release-notes/3.0/preview/api-diff/preview9/README.md
@@ -0,0 +1,7 @@
+# .NET Core 3.0 Preview 9 API Changes
+
+The following API changes were made in .NET Core 3.0 Preview 8:
+
+- [.NET Core](./.Net/3.0-preview9.md)
+- [.NET Core NuGet Packages](./.Net/standalone-packages/3.0-preview9-standalone-packages.md)
+- [ASP.NET Core](./ASP.Net/3.0-preview9.md)