### 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)

picker->set_disabled(p_read_only);
}
void EditorPropertyColor::_color_changed(const Color &p_color) {
	
	if (get_edited_property_value() == p_color) {
		return;
	}
	emit_changed(get_edited_property(), p_color, "", true);
}
void EditorPropertyColor::_popup_closed() {
	if (picker->get_pick_color() != last_color) {
		emit_changed(get_edited_property(), picker->get_pick_color(), "", false);
	}
}
void EditorPropertyColor::_picker_opening() {