[10.0] Migration guidance updates

.openpublishing.redirection.json

@@ -1649,10 +1649,30 @@
             "redirect_url": "/aspnet/core/fundamentals/error-handling-api",
 			"redirect_document_id": false
         },
-		{
+	{
             "source_path": "aspnetcore/fundamentals/map-static-files.md",
             "redirect_url": "/aspnet/core/fundamentals/static-files",
             "redirect_document_id": false
+        },
+	{
+            "source_path": "aspnetcore/migration/60-70.md",
+            "redirect_url": "/aspnet/core/migration/60-to-70",
+            "redirect_document_id": false
+        },
+	{
+            "source_path": "aspnetcore/migration/70-80.md",
+            "redirect_url": "/aspnet/core/migration/70-to-80",
+            "redirect_document_id": false
+        },
+	{
+            "source_path": "aspnetcore/migration/80-90.md",
+            "redirect_url": "/aspnet/core/migration/80-to-90",
+            "redirect_document_id": false
+        },
+	{
+            "source_path": "aspnetcore/migration/20_21.md",
+            "redirect_url": "/aspnet/core/migration/20-to-21",
+            "redirect_document_id": false
         }
     ]
 }

aspnetcore/migration/20_21.md → aspnetcore/migration/20-to-21.md

@@ -5,7 +5,7 @@ description: This article covers the basics of migrating an ASP.NET Core 2.0 app
 ms.author: wpickett
 ms.custom: mvc
 ms.date: 06/09/2019
-uid: migration/20_21
+uid: migration/20-to-21
 ---
 # Migrate from ASP.NET Core 2.0 to 2.1
 

aspnetcore/migration/90-to-100.md

@@ -3,7 +3,7 @@ title: Migrate from ASP.NET Core in .NET 9 to ASP.NET Core in .NET 10
 author: wadepickett
 description: Learn how to migrate an ASP.NET Core in .NET 9 to ASP.NET Core in .NET 10.
 ms.author: wpickett
-ms.date: 8/14/2025
+ms.date: 11/10/2025
 uid: migration/90-to-100
 ---
 # Migrate from ASP.NET Core in .NET 9 to ASP.NET Core in .NET 10

aspnetcore/migration/90-to-100/includes/blazor.md

@@ -1,4 +1,48 @@
-Complete migration coverage for Blazor apps is scheduled for September and October of 2025.
+### Blazor release notes
+
+For new feature coverage, see <xref:aspnetcore-10>.
+
+### Set the Blazor WebAssembly environment with the `WasmApplicationEnvironmentName` MSBuild property
+
+*This section only applies to standalone Blazor WebAssembly apps.*
+
+The `Properties/launchSettings.json` file is no longer used to control the environment in standalone Blazor WebAssembly apps.
+
+Set the environment with the `<WasmApplicationEnvironmentName>` property in the app's project file (`.csproj`).
+
+The following example sets the app's environment to `Staging`:
+
+```xml
+<WasmApplicationEnvironmentName>Staging</WasmApplicationEnvironmentName>
+```
+
+The default environments are:
+
+* `Development` for build.
+* `Production` for publish.
+
+### Boot configuration file inlined
+
+Blazor's boot configuration, which prior to the release of .NET 10 existed in a file named `blazor.boot.json`, has been inlined into the `dotnet.js` script. This only affects developers who are interacting directly with the `blazor.boot.json` file, such as when developers are:
+
+* Checking file integrity for published assets with the troubleshoot integrity PowerShell script per the guidance in <xref:blazor/host-and-deploy/webassembly/bundle-caching-and-integrity-check-failures?view=aspnetcore-9.0#troubleshoot-integrity-powershell-script>.
+* Changing the file name extension of DLL files when not using the default Webcil file format per the guidance in <xref:blazor/host-and-deploy/webassembly/index?view=aspnetcore-9.0#customize-how-boot-resources-are-loaded>.
+
+Currently, there's no documented replacement strategy for the preceding approaches. If you require either of the preceding strategies, open a new documentation issue describing your scenario using the **Open a documentation issue** link at the bottom of either article.
+
+###  Declarative model for persisting state from components and services
+
+In prior Blazor releases, persisting component state during prerendering using the <xref:Microsoft.AspNetCore.Components.PersistentComponentState> service involved a significant amount of code. Starting with .NET 10, you can declaratively specify state to persist from components and services using the `[PersistentState]` attribute. For more information, see <xref:aspnetcore-10#declarative-model-for-persisting-state-from-components-and-services>.
+
+### Custom Blazor cache and `BlazorCacheBootResources` MSBuild property removed
+
+Now that all Blazor client-side files are fingerprinted and cached by the browser, Blazor's custom caching mechanism and the `BlazorCacheBootResources` MSBuild property are no longer available. If the client-side project's project file contains the MSBuild property, remove the property, as it no longer has any effect:
+
+```diff
+- <BlazorCacheBootResources>...</BlazorCacheBootResources>
+```
+
+For more information, see <xref:blazor/host-and-deploy/webassembly/bundle-caching-and-integrity-check-failures?view=aspnetcore-10.0>.
 
 ### Adopt passkey user authentication in an existing Blazor Web App
 

aspnetcore/release-notes/aspnetcore-2.1.md

@@ -166,7 +166,7 @@ For more information, see <xref:mvc/compatibility-version>.
 
 ## Migrate from 2.0 to 2.1
 
-See [Migrate from ASP.NET Core 2.0 to 2.1](xref:migration/20_21).
+See [Migrate from ASP.NET Core 2.0 to 2.1](xref:migration/20-to-21).
 
 ## Breaking changes
 

aspnetcore/security/authentication/scaffold-identity.md

@@ -952,6 +952,6 @@ To prevent publishing static Identity assets to the web root, see <xref:security
 
 ## Additional resources
 
-[Changes to authentication code to ASP.NET Core 2.1 or later](xref:migration/20_21#changes-to-authentication-code)
+[Changes to authentication code to ASP.NET Core 2.1 or later](xref:migration/20-to-21#changes-to-authentication-code)
 
 :::moniker-end

aspnetcore/toc.yml

@@ -2084,6 +2084,9 @@ items:
         uid: migration/index
       - name: Version updates
         items:
+          - name: 9 to 10
+            displayName: migrate, migration
+            uid: migration/90-to-100
           - name: 8 to 9
             displayName: migrate, migration
             uid: migration/80-to-90
@@ -2121,7 +2124,7 @@ items:
                 uid: migration/logging-nonaspnetcore
               - name: 2.0 to 2.1
                 displayName: migrate, migration
-                uid: migration/20_21
+                uid: migration/20-to-21
               - name: 1.x to 2.0
                 displayName: migrate, migration
                 items: