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. 
I throw a bit of their arrogance back in their face if theyre real active in threads, get them to focus on me for awhile instead of derailing multiple threads. My goal is to get them so frustrated they go do something else for awhile. It even works sometimes!