How to cut a map of Russia Yandex maps?

Question

JavaScript

Hello, tell me, pzhst, where to correct,
you need to cut out the map of Russia and hide other countries,
as here
https://tech.yandex.ru/maps/jsbox/2.1/regions_mask

and I get this:

https://jsfiddle.net /svuks/fsc6jhrv/

Answer 1

https://jsfiddle.net/shchedrin/xjtfum6d/