Some very insightful thoughts in that link. I especially liked these two:
"People who provide challenging opinions are not trolling so long as they are not deviating from the conversation at hand. There are some people whose only goal is to attain emotional harmony. When a challenging opinion is encountered it is easy for some people to view this disruption to the social norm as trolling, when it likely isn't."
"Some people are easily offended. When a person engages in a conversation directly without distraction they aren't trolling simply because you became emotional."
https://github.com/prettydiff/wisdom/blob/master/Avoiding_Tr...