### Godot version

4.0-rc6

### System information

Fedora 37, Mesa Intel ADL GT2

### Issue description

Code that works as expected at runtime fails with Nil references to (assigned) exported vars in the editor:

![tool_global_position_error](https://user-images.githubusercontent.com/364501/222031460-ffb1ecbd-5175-4a42-8470-25285ba5f821.png)


### Steps to reproduce

Try to access the `global_position` of a `Node3D` that's assigned to an exported var.

See that it works at runtime.

See that it errors in the editor with:

> Invalid get index 'global_position' (on base: 'Nil').

### Minimal reproduction project

[tool_test.zip](https://github.com/godotengine/godot/files/10856640/tool_test.zip)

RID ci = easing_draw->get_canvas_item();
	Size2 s = easing_draw->get_size();
	const int point_count = 48;
	const float exp = get_edited_property_value();
	const Ref<Font> f = get_theme_font(SNAME("font"), SNAME("Label"));
	int font_size = get_theme_font_size(SNAME("font_size"), SNAME("Label"));
	const Color font_color = get_theme_color(is_read_only() ? SNAME("font_uneditable_color") : SNAME("font_color"), SNAME("LineEdit"));
	Color line_color;
	if (dragging) {
		line_color = get_theme_color(SNAME("accent_color"), SNAME("Editor"));
	} else {
		line_color = get_theme_color(is_read_only() ? SNAME("font_uneditable_color") : SNAME("font_color"), SNAME("LineEdit")) * Color(1, 1, 1, 0.9);
	}
	Vector<Point2> points;
	for (int i = 0; i <= point_count; i++) {