diff --git a/packages/Avalonia/AvaloniaSingleProject.targets b/packages/Avalonia/AvaloniaSingleProject.targets
index 0b8774832f..fc6080154a 100644
--- a/packages/Avalonia/AvaloniaSingleProject.targets
+++ b/packages/Avalonia/AvaloniaSingleProject.targets
@@ -176,6 +176,8 @@
   </Target>
 
   <!-- IDE capabilities -->
+  <!-- Keep synced with https://github.com/dotnet/maui/blob/f0c4dd19d4c4cba7c6060ec5ceb8ba150bbdf9a5/src/Workload/Microsoft.Maui.Sdk/Sdk/Microsoft.Maui.Sdk.After.targets#L25 -->
+  <!-- Otherwise Visual Studio single project support might be broken. -->
   <ItemGroup Condition=" '$(AvaloniaSingleProject)' == 'true' ">
     <ProjectCapability Include="Msix" />
     <ProjectCapability Include="MauiSingleProject" />
@@ -185,6 +187,12 @@
     <!-- Otherwise define LaunchProfilesGroupByPlatformFilters by default -->
     <ProjectCapability Include="LaunchProfilesGroupByPlatformFilters" Condition=" '$(VisualStudioVersion)' == '' or '$(VisualStudioVersion)' &gt;= '17.0' " />
     <ProjectCapability Include="SingleTargetBuildForStartupProjects" Condition=" '$(EnableSingleTargetBuildForStartupProjects)' != 'false' " />
+
+    <ProjectCapability Include="UseMauiCore" />
+
+    <!-- .NET MAUI features (also required for single project) -->
+    <ProjectCapability Include="MauiCore" />
+    <ProjectCapability Include="Maui" />
   </ItemGroup>
 
   <!-- Android -->
diff --git a/samples/MobileSandbox/MobileSandbox.csproj b/samples/MobileSandbox/MobileSandbox.csproj
index cfb3f41225..e745f4b6da 100644
--- a/samples/MobileSandbox/MobileSandbox.csproj
+++ b/samples/MobileSandbox/MobileSandbox.csproj
@@ -23,6 +23,11 @@
     <ProjectReference Include="..\SampleControls\ControlSamples.csproj" />
   </ItemGroup>
 
+  <ItemGroup>
+    <!-- Only useful in VS, but https://www.vsixcookbook.com/tips/projects.html -->
+    <ProjectCapability Include="DiagnoseCapabilities" />
+  </ItemGroup>
+
   <Import Project="..\..\build\BuildTargets.targets" />
   <Import Project="..\..\build\SourceGenerators.props" />
 </Project>