The kind that thinks communism is the same as nazism and thinks communism is when the government does things.
I hate liberal brain worms.
They seriously do as much damage to the left as fascists by punching to the left and spreading capitalist anti-left propaganda. They overall weaken leftism and help fascism.
We need more left unity, folks. Fash ain't gonna bash themselves. 
Hexbear scholars have put forth a compelling white paper which dispels all of these anti-tankie arguments
Self identified anti-tankies can find it at https://hexbear.net/PPB