The words "troll" and "trolling" are stale metaphors, and should be retired.
Because:
Used too much, says Orwell, a metaphor loses its force, people forget what they mean, and fall into nonsense.
It's boring. Find another way to criticize the heretic.
It is unclear. Does it mean a left-winger has said something left-wing on a right-wing page? Or right-wing on a left-wing page? Or something that she disbelieves, simply to irritate people?
It's better to refute the errors than call the person a name.
We need critics. All of us.
Occasionally, even a commie or a Nazi or an Objectivist or HR or even the flack for an ice-cream eating over-the-hill crook might say something true. In that case, we can learn from "the troll." Because right-wingers and Christians get things wrong, too, God bless them every one.