### 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 (_is_grid_visible()) {
		
		Vector2 real_grid_offset;
		const List<CanvasItem *> selection = _get_edited_canvas_items();
		if (snap_relative && selection.size() > 0) {
			const Vector2 topleft = _get_encompassing_rect_from_list(selection).position;
			real_grid_offset.x = fmod(topleft.x, grid_step.x * (real_t)Math::pow(2.0, grid_step_multiplier));
			real_grid_offset.y = fmod(topleft.y, grid_step.y * (real_t)Math::pow(2.0, grid_step_multiplier));
		} else {
			real_grid_offset = grid_offset;
		}
		
		
		const Color secondary_grid_color = EDITOR_GET("editors/2d/grid_color");
		const Color primary_grid_color =
				Color(secondary_grid_color.r, secondary_grid_color.g, secondary_grid_color.b, secondary_grid_color.a * 2.5);
		const Size2 viewport_size = viewport->get_size();
		const Transform2D xform = transform.affine_inverse();
		int last_cell = 0;
		if (grid_step.x != 0) {
			for (int i = 0; i < viewport_size.width; i++) {
				const int cell =
						Math::fast_ftoi(Math::floor((xform.xform(Vector2(i, 0)).x - real_grid_offset.x) / (grid_step.x * Math::pow(2.0, grid_step_multiplier))));
				if (i == 0) {
					last_cell = cell;
				}
				if (last_cell != cell) {
					Color grid_color;
					if (primary_grid_steps == 0) {
						grid_color = secondary_grid_color;