Nighttime Export has missing references on default export

[BenjaminGroseclose]

When exporting the default theme RevealBackgroundSource element is not found, as well as BackgroundSource property on the AcrylicBrush element is not found.

Environment:

  <PropertyGroup>
    <OutputType>WinExe</OutputType>
    <TargetFramework>net5.0-windows10.0.19041.0</TargetFramework>
    <TargetPlatformMinVersion>10.0.17763.0</TargetPlatformMinVersion>
    <RootNamespace>Test.Application</RootNamespace>
    <ApplicationManifest>app.manifest</ApplicationManifest>
    <Platforms>x86;x64;arm64</Platforms>
    <RuntimeIdentifiers>win10-x86;win10-x64;win10-arm64</RuntimeIdentifiers>
    <UseWinUI>true</UseWinUI>
    <SupportedOSPlatformVersion>10.0.17763.0</SupportedOSPlatformVersion>
  </PropertyGroup>

  <ItemGroup>
    <PackageReference Include="CommunityToolkit.Mvvm" Version="7.0.3" />
    <PackageReference Include="CommunityToolkit.WinUI.UI.Controls" Version="7.0.3" />
    <PackageReference Include="Microsoft.Extensions.DependencyInjection" Version="5.0.2" />
    <PackageReference Include="Microsoft.ProjectReunion" Version="0.8.5" />
    <PackageReference Include="Microsoft.ProjectReunion.Foundation" Version="0.8.5" />
    <PackageReference Include="Microsoft.ProjectReunion.WinUI" Version="0.8.5" />
    <Manifest Include="$(ApplicationManifest)" />
  </ItemGroup>