diff --git a/eng/Versions.props b/eng/Versions.props
index 402c63052d6..99c05d2ed5f 100644
--- a/eng/Versions.props
+++ b/eng/Versions.props
@@ -102,7 +102,7 @@
     <!-- Roslyn packages. Rest is managed by maestro bot and is in the imported .Details.props file -->
     <MicrosoftCodeAnalysisTestResourcesProprietaryVersion>2.0.28</MicrosoftCodeAnalysisTestResourcesProprietaryVersion>
 	  <!-- Roslyn for when we need to compile C# in tests. .dll hell caused by vstest makes newer version fail at runtime -->
-	  <RoslynForTestingButNotForVSLayer>4.14.0</RoslynForTestingButNotForVSLayer>
+	  <RoslynForTestingButNotForVSLayer>5.0.0-2.25480.7</RoslynForTestingButNotForVSLayer>
     <!-- -->
     <!-- Visual Studio Shell packages -->
     <MicrosoftVisualStudioInteropVersion>$(MicrosoftVisualStudioShellPackagesVersion)</MicrosoftVisualStudioInteropVersion>
diff --git a/vsintegration/tests/Salsa/VisualFSharp.Salsa.fsproj b/vsintegration/tests/Salsa/VisualFSharp.Salsa.fsproj
index f7410214430..390088dfd47 100644
--- a/vsintegration/tests/Salsa/VisualFSharp.Salsa.fsproj
+++ b/vsintegration/tests/Salsa/VisualFSharp.Salsa.fsproj
@@ -39,6 +39,7 @@
     <ProjectReference Include="..\..\src\FSharp.LanguageService\FSharp.LanguageService.fsproj" />
     <ProjectReference Include="..\..\src\FSharp.ProjectSystem.Base\FSharp.ProjectSystem.Base.csproj" />
     <ProjectReference Include="..\..\src\FSharp.ProjectSystem.FSharp\FSharp.ProjectSystem.FSharp.fsproj" />
+    <ProjectReference Include="..\..\..\tests\FSharp.Test.Utilities\FSharp.Test.Utilities.fsproj" />
   </ItemGroup>
 
   <ItemGroup>
diff --git a/vsintegration/tests/Salsa/VsMocks.fs b/vsintegration/tests/Salsa/VsMocks.fs
index 5189b7faec5..12108b08421 100644
--- a/vsintegration/tests/Salsa/VsMocks.fs
+++ b/vsintegration/tests/Salsa/VsMocks.fs
@@ -1640,6 +1640,7 @@ module internal VsActual =
     open System.IO
     open System.ComponentModel.Composition.Hosting
     open System.ComponentModel.Composition.Primitives
+    open FSharp.Test.VSInstallDiscovery
     open Microsoft.VisualStudio.Text
     open Microsoft.VisualStudio.Threading
 
@@ -1651,15 +1652,18 @@ module internal VsActual =
         member public _.JoinableTaskContext : JoinableTaskContext = jtc
 
     let vsInstallDir =
-        // use the environment variable to find the VS installdir
-        let vsvar =
-            let var = Environment.GetEnvironmentVariable("VS170COMNTOOLS")
-            if String.IsNullOrEmpty var then
-                Environment.GetEnvironmentVariable("VSAPPIDDIR")
-            else
-                var
-        if String.IsNullOrEmpty vsvar then failwith "VS170COMNTOOLS and VSAPPIDDIR environment variables not found."
-        Path.Combine(vsvar, "..")
+        match tryGetVSInstallDir () with
+        | Some dir -> dir
+        | None ->
+            // Fallback to legacy behavior for backward compatibility
+            let vsvar =
+                let var = Environment.GetEnvironmentVariable("VS170COMNTOOLS")
+                if String.IsNullOrEmpty var then
+                    Environment.GetEnvironmentVariable("VSAPPIDDIR")
+                else
+                    var
+            if String.IsNullOrEmpty vsvar then failwith "VS170COMNTOOLS and VSAPPIDDIR environment variables not found."
+            Path.Combine(vsvar, "..")
 
     let CreateEditorCatalog() =
         let thisAssembly = Assembly.GetExecutingAssembly().Location