OldJsonPlugin.csproj

<Project Sdk="Microsoft.NET.Sdk">

  <PropertyGroup>
    <TargetFramework>net5</TargetFramework>
  </PropertyGroup>

  <ItemGroup>
    <PackageReference Include="Newtonsoft.Json" Version="13.0.1" />
  </ItemGroup>

  <ItemGroup>
    <ProjectReference Include="..\PluginBase\PluginBase.csproj">
      <Private>false</Private>
      <ExcludeAssets>runtime</ExcludeAssets>
    </ProjectReference>
  </ItemGroup>

</Project>