There's an interesting shift in language associated with the Russian invasion of Ukraine - a type of pierogi which used to be called ruskie (from the region of Red Rus, where they originate) are now commonly named ukraińskie (Ukrainian) instead. The reason is that the adjective ruskie is typically understood as "Russian" in general parlance.
My friend told me "ruskie" is used as a somewhat pejorative description of a "Russian". Like Brits say "Yanks" about the Americans. The other issue is that people don't know how to translate "ruski" to English, so they would say "Russian dumplings", but in reality they should be called "Ruthenian dumplings" from Ruthenian Voivodeship. They probably seen tourists turn their nose on "Russian dumplings", so they renamed…
When it's used as a noun it's pejorative for Russian people. When it's used as an adjective - it's neutral (and can be used both for russian and ruthenian stuff).
There's also more specific words - rosyjskie for russian and rusińskie for ruthenian, but very few people use "rusińskie" nowadays.
BTW there's this joke from communist times:
A waitress in a milk bar shouts "who ordered ruskie", someone in the bar shouts back "nobody, they came on their own".