If you have multiple outputs lets do something a little different.

Instead of storing the cursor::Handle in CompositorState try storing it in the OutputHandler. This will give each output its own cursor. You should add a keybinding to switch what the "current" one is.

If you have multiple input devices hanging around then lets get a little crazy.

Instead of storing the cursor::Handle in CompositorState try storing it in the PointerHandler. This will allow each pointer to have its own, separate cursor.

If you have multiple outputs you probably noticed that the cursor can reach across all of them. However, it is probably not going across the correct edge since wlroots has no way to know how the monitors are physically set up in the world.

Using the non-auto functions in output::Layout, and a configuration description of your choice make it possible for the user to set up their outputs how they like.

Without endorsing any particular configuration format, it is suggested that you nevertheless use serde as that is the standard way in Rust to encode and decode arbitrary formats.