It just means "white left". It's a Chinese word used by even the Chinese Left. It's used to describe SJW values, mainly those of white saviorism. The Chinese hate the Western SJW culture too. Since they will try to side with China, use it to trigger cognitive dissonance.
Also throw "wumao" at the CCP shills. It's the phrase used to describe the CCP's 50 cent army that types anti-American stuff all day. It's a legitimate thing to use, unlike "Russian bot".
i prefer faggot or dumb nigger, plus I dont want to get accused of cultural appropriation.