diff --git a/CHANGELOG.md b/CHANGELOG.md
index 9a6e567854..d0929dbf04 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -4,7 +4,15 @@
 - Debug from .csproj and .sln [#5876](https://github.com/dotnet/vscode-csharp/issues/5876)
 
 # 2.90.x
-* Bump Razor to 10.0.0-preview.25416.1 (PR: [#8557](https://github.com/dotnet/vscode-csharp/pull/8557))
+* Bump Roslyn to 5.0.0-2.25424.1 (PR: [#8559](https://github.com/dotnet/vscode-csharp/pull/8559))
+  * Generate `init` accessor for required properties inside `readonly struct`s (PR: [#80004](https://github.com/dotnet/roslyn/pull/80004))
+  * Allow Razor cohosting to work with non-Razor SDK projects (PR: [#79953](https://github.com/dotnet/roslyn/pull/79953))
+  * Update 'use expr body' to be a purely syntactic analyzer (PR: [#79979](https://github.com/dotnet/roslyn/pull/79979))                                                                                                                                 
+  * Implement "Simplify property accessor" feature (PR: [#79754](https://github.com/dotnet/roslyn/pull/79754))                                                                                                               
+  * Allow Razor to hook up the source generator in misc files (PR: [#79891](https://github.com/dotnet/roslyn/pull/79891))
+* Bump Razor to 10.0.0-preview.25424.9 (PR: [#8559](https://github.com/dotnet/vscode-csharp/pull/8559))
+  * Allow Razor cohosting to work with non-Razor SDK projects (PR: [#12118](https://github.com/dotnet/razor/pull/12118))
+  * Allow the source generator to produce results for miscellaneous files (PR: [#12106](https://github.com/dotnet/razor/pull/12106))
   * Fix range formatting in the presence of K&R braces (PR: [#12121](https://github.com/dotnet/razor/pull/12121))
   * Add codelens endpoints and services for cohosting (PR: [#12078](https://github.com/dotnet/razor/pull/12078))
   * Support Go To Def for Mvc tag helpers in cohosting (PR: [#12102](https://github.com/dotnet/razor/pull/12102))
diff --git a/package.json b/package.json
index 7ef1eab978..c96baf7055 100644
--- a/package.json
+++ b/package.json
@@ -40,9 +40,9 @@
     "workspace"
   ],
   "defaults": {
-    "roslyn": "5.0.0-2.25412.5",
-  "omniSharp": "1.39.14",
-    "razor": "10.0.0-preview.25419.3",
+    "roslyn": "5.0.0-2.25424.1",
+    "omniSharp": "1.39.14",
+    "razor": "10.0.0-preview.25424.9",
     "razorOmnisharp": "7.0.0-preview.23363.1",
     "xamlTools": "17.14.36106.43"
   },
diff --git a/src/lsptoolshost/server/roslynLanguageServer.ts b/src/lsptoolshost/server/roslynLanguageServer.ts
index 1171b196a4..8d1951d1f4 100644
--- a/src/lsptoolshost/server/roslynLanguageServer.ts
+++ b/src/lsptoolshost/server/roslynLanguageServer.ts
@@ -666,7 +666,7 @@ export class RoslynLanguageServer {
 
         args.push(
             '--razorDesignTimePath',
-            path.join(razorPath, 'Targets', 'Microsoft.NET.Sdk.Razor.DesignTime.targets')
+            path.join(razorSourceGeneratorPath, 'Targets', 'Microsoft.NET.Sdk.Razor.DesignTime.targets')
         );
 
         // Get the brokered service pipe name from C# Dev Kit (if installed).
@@ -706,6 +706,15 @@ export class RoslynLanguageServer {
             // Set command enablement to use roslyn standalone commands.
             await vscode.commands.executeCommand('setContext', 'dotnet.server.activationContext', 'Roslyn');
             _wasActivatedWithCSharpDevkit = false;
+
+            if (razorOptions.cohostingEnabled) {
+                // Razor has code in Microsoft.CSharp.DesignTime.targets to handle non-Razor-SDK projects, but that doesn't get imported outside
+                // of DevKit so we polyfill with a mini-version that Razor provides for that scenario.
+                args.push(
+                    '--csharpDesignTimePath',
+                    path.join(razorComponentPath, 'Targets', 'Microsoft.CSharpExtension.DesignTime.targets')
+                );
+            }
         }
 
         for (const extensionPath of additionalExtensionPaths) {