Can not resolve reference: `System.Threading.Tasks.Extensions`

[runceel]

This issue is related: dotnet/reactive#803

[ChrisPulman]

I believe this is specifically related to Android Projects and something strange happening with Nuget when you add System.Reactive

[ChrisPulman]

The root cause is in package System.Threading.Tasks.Extensions there are no dll's in the targets other than NetStandard2.0

A temporary resolution could be to add the following to your project file manually

<ItemGroup>
    <PackageReference Include="System.Runtime.CompilerServices.Unsafe" Version="4.5.2"/>
  </ItemGroup>
  <ItemGroup>
    <Reference Include="System.Threading.Tasks.Extensions">
      <HintPath>$(UserProfile)\.nuget\packages\system.threading.tasks.extensions\4.5.1\lib\netstandard2.0\System.Threading.Tasks.Extensions.dll</HintPath>
    </Reference>
  </ItemGroup>

[runceel]

Thank you for workaround information.
I'll wait the issues will be fixed.

Your workaround is very useful for this issues, so I open the issue until fixed.

[runceel]

It was fixed on latest Xamarin.Android.
I've checked the issue is not occurred on Visual Studio 2019.