diff --git a/build/MSBuildExtensions.targets b/build/MSBuildExtensions.targets
index 1a2e75e2f..9c5f30923 100644
--- a/build/MSBuildExtensions.targets
+++ b/build/MSBuildExtensions.targets
@@ -156,6 +156,7 @@ Copyright (c) .NET Foundation. All rights reserved.
 
     
     <KnownFrameworkReference Include="Microsoft.DesktopUI"
+                              TargetFramework="netcoreapp3.0"
                               RuntimeFrameworkName="Microsoft.DesktopUI.App"
                               DefaultRuntimeFrameworkVersion="$(MicrosoftDesktopUIPackageVersion)"
                               LatestRuntimeFrameworkVersion="$(MicrosoftDesktopUIPackageVersion)"
@@ -164,6 +165,7 @@ Copyright (c) .NET Foundation. All rights reserved.
                               />
 
     <KnownFrameworkReference Include="Microsoft.AspNetCore"
+                              TargetFramework="netcoreapp3.0"
                               RuntimeFrameworkName="Microsoft.AspNetCore.App"
                               DefaultRuntimeFrameworkVersion="$(MicrosoftAspNetCoreAppPackageVersion)"
                               LatestRuntimeFrameworkVersion="$(MicrosoftAspNetCoreAppPackageVersion)"