[Feature Request] Span a window across monitors

**Describe the feature you'd like**
I don't know whether this is possible or within the scope of this extension, but it would be quite nice to have the ability to create a layout across multiple monitors and then assign windows to it. The use-case I have has me using an app that does not support multiple windows itself but does support in-window splits, thus I want to have it span two monitors to have the width.