Monogame blocks / consumes Keyboard Input, how to disable this?

I have a WPF window and start a Monogame instance from it. I need monogame just for rendering into a Rendertarget2D. But as soon as I start Monogame it consumes my keyboard input and I can’t use text input in my WPF window anymore.

So how can I prevent Monogame from consuming/blocking the keyboard keys?

I think it is related to my post (first post is related to second where they are looking into it):