“Following recent regulatory changes in Russia, we received persistent requests from Roskomnadzor demanding that five add-ons be removed from the Mozilla add-on store,” a Mozilla spokesperson told The Intercept in response to a request for comment. “After careful consideration, we’ve temporarily restricted their availability within Russia."
It sucks, but it's a battle they weren't ever going to win. The dictator gets to have final say in how things go in their country.