### 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
if (ci->get_viewport() != EditorNode::get_singleton()->get_scene_root()) {
			continue;
		}
		if (Object::cast_to<Node2D>(ci)) {
			Node2D *n2d = Object::cast_to<Node2D>(ci);
			if (key_pos && p_location) {
				te->insert_node_value_key(n2d, "position", n2d->get_position(), p_on_existing);
			}
			if (key_rot && p_rotation) {
				te->insert_node_value_key(n2d, "rotation", n2d->get_rotation(), p_on_existing);
			}
			if (key_scale && p_scale) {
				te->insert_node_value_key(n2d, "scale", n2d->get_scale(), p_on_existing);
			}
			if (n2d->has_meta("_edit_bone_") && n2d->get_parent_item()) {
				//look for an IK chain
				List<Node2D *> ik_chain;
				Node2D *n = Object::cast_to<Node2D>(n2d->get_parent_item());
				bool has_chain = false;
				while (n) {
					ik_chain.push_back(n);
					if (n->has_meta("_edit_ik_")) {
						has_chain = true;
						break;
					}
					if (!n->get_parent_item()) {
						break;
					}
					n = Object::cast_to<Node2D>(n->get_parent_item());
				}