### Godot version

v4.0.beta.custom_build [eaf306e0b]

### System information

Windows 10

### Issue description

Selecting a `Window` node in the Editor's SceneTree results in the message
```
editor/editor_data.cpp:1058 - Parameter "p_node" is null.
```
and the Inspector shows empty content instead of the Window's properties.

I would expect, that clicking on a node in the SceneTree lets me edit the properties of the node.

Bisecting shows that this behavior got introduced in #71770

### Steps to reproduce

1. Create a Window node
2. Click on the Window node in the Editor's SceneTree

### Minimal reproduction project

N/A
}
			}
		} else {
			changed = true;
		}
		if (changed) {
			hovering_results = hovering_results_tmp;
			viewport->queue_redraw();
		}
		return true;
	}
	return false;
}
void CanvasItemEditor::_gui_input_viewport(const Ref<InputEvent> &p_event) {
	bool accepted = false;
	Ref<InputEventMouseButton> mb = p_event;
	bool release_lmb = (mb.is_valid() && !mb->is_pressed() && mb->get_button_index() == MouseButton::LEFT); 
	if (EDITOR_GET("editors/panning/simple_panning") || !pan_pressed || release_lmb) {
		accepted = true;
		if (_gui_input_rulers_and_guides(p_event)) {
			
		} else if (EditorNode::get_singleton()->get_editor_plugins_over()->forward_gui_input(p_event)) {
			
		} else if (_gui_input_open_scene_on_double_click(p_event)) {
			
		} else if (_gui_input_scale(p_event)) {
			
		} else if (_gui_input_pivot(p_event)) {
			
		} else if (_gui_input_resize(p_event)) {