I have an asp.net core application that uses out of process PowerShell.

Steps to reproduce

Create a project with the following code:

using System;
using System.Management.Automation.Runspaces;

PowerShellProcessInstance instance = new PowerShellProcessInstance(
                powerShellVersion: new Version(5, 1),
                credential: null,
                initializationScript: null,
                useWow64: false
);
var runspace = RunspaceFactory.CreateOutOfProcessRunspace(null, instance);
runspace.Open();

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

  <PropertyGroup>
    <OutputType>Exe</OutputType>
    <TargetFramework>net5.0</TargetFramework>
  </PropertyGroup>

  <ItemGroup>
    <PackageReference Include="system.management.automation" Version="7.0.3" />
  </ItemGroup>

</Project>

Note, also happens w ith System.Management.Automation 7.1.0 (most recent rc)

Expected behavior

Runspace opens properly.

Actual behavior

An exception is raised:

An error has occurred which PowerShell cannot handle. A remote session might have ended.

Inner exception:

BinaryFormatter serialization and deserialization are disabled within this application. See https://aka.ms/binaryformatter for more information.

Additional details

1. The issue does not occur when using the default project sdk (not the web one)
2. BinaryFormatter should probably not be used, see BinaryFormatter long-term obsoletion plan dotnet/designs#141