Create a new window in WPF (.xaml and .xaml.cs)

Hello,

It's been a while since I started C # with Visual Studio. Since a few months, I started on Rider and I must say that I really appreciate this software.
 
However, I have a small problem with the software. Maybe I'm doing wrong, but in a C # project (WPF), I see no way to create a new window, that is to say to provide a .xaml create and .xaml.cs file.

I made a small screenshot of my menu Add.

The question is: How to create a new window in Rider ?

PS: I'm on the latest version of Rider, the 2018.1.1

Thank you,
Regards,
Whiskey