### Godot version

4.1 dev2, 4.0.3

### System information

Windows 10, ryzen 5900x, radeon 6950xt (driver: 23.2.2)

### Issue description

There are two bugs:
- When I create a new node, it is created outside of the viewport. (as in first video)
- When I run the project, all the content inside the viewport dont appear. (as in second video)
I believe the second issue is related to the first.

Note: these problems are in RTL editors.

https://github.com/godotengine/godot/assets/121864036/84f0d434-0d1b-4c23-9fb0-510257e2e191


https://github.com/godotengine/godot/assets/121864036/b2bc20c7-1e2e-4d04-99e7-d66860ffced2




### Steps to reproduce

Videos explain.

### Minimal reproduction project

N/A
ERR_READ_THREAD_GUARD_V(false);
	return data.theme_owner->has_owner_node();
}
void Control::set_theme(const Ref<Theme> &p_theme) {
	ERR_MAIN_THREAD_GUARD;
	if (data.theme == p_theme) {
		return;
	}
	if (data.theme.is_valid()) {
		data.theme->disconnect("changed", callable_mp(this, &Control::_theme_changed));
	}
	data.theme = p_theme;
	if (data.theme.is_valid()) {
		data.theme_owner->propagate_theme_changed(this, this, is_inside_tree(), true);
		data.theme->connect("changed", callable_mp(this, &Control::_theme_changed), CONNECT_DEFERRED);
		return;
	}
	Control *parent_c = Object::cast_to<Control>(get_parent());
	if (parent_c && parent_c->has_theme_owner_node()) {
		data.theme_owner->propagate_theme_changed(this, parent_c->get_theme_owner_node(), is_inside_tree(), true);
		return;
	}
	Window *parent_w = cast_to<Window>(get_parent());
	if (parent_w && parent_w->has_theme_owner_node()) {
		data.theme_owner->propagate_theme_changed(this, parent_w->get_theme_owner_node(), is_inside_tree(), true);
		return;
	}
	data.theme_owner->propagate_theme_changed(this, nullptr, is_inside_tree(), true);
}
Ref<Theme> Control::get_theme() const {