Project file cannot specify more than one ApplicationDefinition element.

Here's the projectfile: <Project Sdk="Microsoft.NET.Sdk.WindowsDesktop"> <PropertyGroup> <OutputType>WinExe</OutputType> <TargetFramework>net7.0-windows</TargetFramework> <UseWPF>true</UseWPF> <UseWindowsForms>false</UseWindowsForms> <!-- Set to false if not needed --> <UserSecretsId>d94128a5-5451-4db6-8f2a-22edfcc31b3c</UserSecretsId> <RootNamespace>ListenUp</RootNamespace> <AssemblyName>ListenUp</AssemblyName> <SignAssembly>false</SignAssembly> <PlatformTarget>x64</PlatformTarget> </PropertyGroup> <ItemGroup> <ApplicationDefinition Include="App.xaml" /> </ItemGroup> <ItemGroup> <PackageReference Include="Microsoft.CSharp" Version="4.7.0" /> <PackageReference Include="Microsoft.Extensions.Configuration.UserSecrets" Version="8.0.0" /> <PackageReference Include="System.ComponentModel.Composition" Version="8.0.0" /> <PackageReference Include="System.Data.DataSetExtensions" Version="4.5.0" /> </ItemGroup> <ItemGroup> <ProjectReference Include="..\TypeWriter\typewriterupgraded\typewriterupgraded.csproj" /> </ItemGroup> <ItemGroup> <Resource Include="25394.png"> <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory> </Resource> <Resource Include="TheWeeknd-_Blinding_Lights.png" /> </ItemGroup> <ItemGroup> <Compile Update="Properties\Settings.Designer.cs"> <DesignTimeSharedInput>true</DesignTimeSharedInput> <AutoGen>true</AutoGen> <DependentUpon>Settings.settings</DependentUpon> </Compile> </ItemGroup> <ItemGroup> <None Update="Properties\Settings.settings"> <Generator>SettingsSingleFileGenerator</Generator> <LastGenOutput>Settings.Designer.cs</LastGenOutput> </None> </ItemGroup> </Project>