Communism is the theory. Fascism is the practice

 Just ask the dumbest LLM

https://www.marxists.org/archive/marx/works/1848/communist-manifesto/

Some post Lenin, Marxist-Communist types later plumped for race over class, even as both were covered by the mature ideology.

Capital, vol. 3, chapter 47: "The possibility is here presented for definite economic development taking place, depending, of course, upon favourable circumstances, inborn racial characteristics, etc."

Engels: (Marx and Engels, Selected Works, Vol. 3, p. 502.): "We regard economic conditions as the factor which ultimately determines historical development. But race is itself an economic factor".