title: How can I add WPF items into a C# class library project in VS2019?
body: <p>I have started a Class library project in Visual Studio 2019 and now wish to add WPF items (Window, user control, custom control) into it, but the 'Add Item' dialog box doesn't list anything under the WPF section.</p>
  <p>I have come across this problem in previous versions of VS and managed to get around it by adding the <code>&lt;ProjectTypeGuids&gt;</code> element into the csproj file with the relevant WPF GUIDs. However, that doesn't appear to work with the new VS2019 stripped down csproj file, or I don't know where to find the correct GUIDs (as I have only tried using those I used before).</p>
  <p>Does anyone know the correct process to follow for VS2019?</p>
  <p>P.S. I am aware that this question appears to have been answered before (for example <a href="https://stackoverflow.com/questions/3573339/no-creation-of-a-wpf-window-in-a-dll-project">No creation of a WPF window in a DLL project</a>), but as far as I can tell, they are all for previous versions of Visual Studio and the suggestions don't work for me.</p>