@LeP
Yes, but Russian IS an international language, I am afraid: my wife from Lithuania is fluent and I am proficient. Just like many others that have a history with the former soviet union, its former states and affiliate states, not different from English. It is not common to this forum (although it is... a bit) but should not distract from good code.
There are more Russian speakers outside of Russia than in Russia.
But I can see your discomfort and mostly the forum is managed as such: there is a Russian subforum.
But Russian in the code comments should never be a problem.