Wpf: System.Windows.Forms.FolderBrowserDialog no longer compiles in WPF app

[skanvk15]

• .NET Core Version: (e.g. 3.0 Preview1, or daily build number, use dotnet --info)
  Microsoft.NETCore.App 3.0.0-preview7-27912-14 [C:Program FilesdotnetsharedMicrosoft.NETCore.App]
  Microsoft.WindowsDesktop.App 3.0.0-preview7-27912-14 [C:Program FilesdotnetsharedMicrosoft.WindowsDesktop.App]

• Windows version: (winver)
  Windows 10

• Does the bug reproduce also in WPF for .NET Framework 4.8?: Yes/No
  N/A

Problem description:
I used to be able to use the Win Forms folder dialog in .NET Core 3.0 Preview version WPF app, like this:
System.Windows.Forms.FolderBrowserDialog folderBrowserDialog;
But with latest .NET Core 3.0 Preview version I get compiler error.

Actual behavior:
I get this compiler error:
error CS0234: The type or namespace name 'Forms' does not exist in the namespace 'System.Windows' (are you missing an assembly reference?)

Expected behavior:
No error

Minimal repro:
Create new .NET Core WPF app and update MainWindow constructor like this:
public MainWindow() { InitializeComponent(); System.Windows.Forms.FolderBrowserDialog folderBrowserDialog; }

[0xd4d]

Make sure you have this in your csproj file:

  <PropertyGroup>
    <UseWPF>true</UseWPF>
    <UseWindowsForms>true</UseWindowsForms>
  </PropertyGroup>

[skanvk15]

Thanks that fixed it!

[msyusuf]

Thanks, it fixed it for me too.