### 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)

}
void EditorPropertyTextEnum::_notification(int p_what) {
	switch (p_what) {
		case NOTIFICATION_ENTER_TREE:
		case NOTIFICATION_THEME_CHANGED: {
			edit_button->set_icon(get_theme_icon(SNAME("Edit"), SNAME("EditorIcons")));
			accept_button->set_icon(get_theme_icon(SNAME("ImportCheck"), SNAME("EditorIcons")));
			cancel_button->set_icon(get_theme_icon(SNAME("ImportFail"), SNAME("EditorIcons")));
		} break;
	}
}
EditorPropertyTextEnum::EditorPropertyTextEnum() {
	HBoxContainer *hb = memnew(HBoxContainer);
	add_child(hb);
	default_layout = memnew(HBoxContainer);
	default_layout->set_h_size_flags(SIZE_EXPAND_FILL);
	hb->add_child(default_layout);
	edit_custom_layout = memnew(HBoxContainer);
	edit_custom_layout->set_h_size_flags(SIZE_EXPAND_FILL);
	edit_custom_layout->hide();
	hb->add_child(edit_custom_layout);
	option_button = memnew(OptionButton);