Xaml UI Designer is inactive for wpf projects in .net core 3.0

Question

I have updated Visual Studio 2019 to version 16.3 which can support .Net Core 3 stable version.

After creating the first WPF app supported by .Net Core 3, the desig

Answer 1

I ran into this same issue with Visual Studio Community 2019 Version 16.4.3 and a .NET Core 3.1 WPF project.

It turns out that JetBrains ReSharper was causing the problem as it automatically disables the XAML Designer. To change this behavior, navigate to Extensions/ReSharper/Options, search for Disable XAML designer and set the Action dropdown to Ignore.

Then, as Jon mentioned, make sure to check Enable XAML Designer under Tools/Options/XAML Designer. Restart Visual Studio and you should be good to go.