Pro-secessionist, or "separatist"activities are frowned by the Russian authorities. They are a good way of attracting attention by the FSB and if coupled with calls for unilateral action getting oneself into legal trouble.
Nonetheless, Russia would not be the only state in the world that occasionally indulges in a little bit hypocrisy -- especially when the outcome is this hilarious (and harmless).
The Yes California Independence movement has opened their first office abroad now -- in Moscow. Promoting independence of Russian regions is a suspicious activity, but promoting independence of American states -- now that sounds like a fun thought. Russia’s state-run news agency, Rossiya Segodnya, certainly thought so and showed up for the opening and the accompanying press conference.
Recently Syrian Kurds have been allowed to open an office in Moscow which was the much more geopolitically significant event -- a warning sign to Erdogan that Russia has options and it would not be wise to antagonize it.
The 'California embassy' by comparison sounds more like a mischievous curiosity and the the result of a crusade by one man, Louis Marinelli, the founder of the Yes California Independence Campaign:
Mr. Marinelli, 30, has been one of the most vocal proponents in recent years of the grassroots movement dedicated towards gaining California’s independence from the United States. He’s orchestrated that campaign from abroad since at least September, however, when he relocated from San Diego to Siberia to be with his Russian wife, KQED recently reported.
The story was covered in the US by Business Insider and Washington Times -- neither of which could work up much outrage over it. So far the only western outlet triggered by the news has been The Moscow Times which deemed the office "a bizarre facility" and denounced Marinelli as a "separatist" in the very opening statement of its report.
Today the Embassy of the Independent Republic of California opens in Moscow. Address: Г. Москва, ул. Клары Цеткин дом 4, Офис 324. #Calexit— CA Embassy Moscow (@CAEmbRu)December 18, 2016
In any case it seems that if a campaign for a California independence referendum will go anywhere the Russians will have front row seats for the spectacle -- and no doubt popcorn ready.