The question of “bad faith engagement” is important and I think it’s worth discussing, but I think it’s also important that it start at the very beginning.
What is the point of an online community? Of a community at all, really? We all have different purposes, but speaking for me, my main purpose in seeking community is to find like-minded people with whom I can grow and also to whom I can provide help in their own journey of growth. We use different vehicles to achieve this, be it shitposting hilarious memes or engaging in earnest navel-gazing discussion, but ultimately my personal goal (and I suspect the goal of many) is to truly connect with someone else in an effort to understand and be understood.
So rather than talk about “bad faith,” I think it’s important to define what “good faith” is. If we accept the above premise about seeking connection and growth, then generally it involves honestly representing yourself and what you stand for to others. We compartmentalize discussions as a way to focus our values through a specific lens, and in having many such discussions we can discover many facets of each other (and ourselves in the process). Engaging in good faith means that you are forthright in that representation, because we are proceeding from the assumption that each person here wants to be known to others and wants to grow - and that won’t happen if you aren’t honest in what you’re about.
So then “bad faith” engagement is anything that isn’t an attempt at “good faith” engagement. The question you should ask isn’t “what should I not do,” it’s “what should I do to honestly represent myself?”
Not all bad faith engagements are equally bad - see the above commentary about sarcasm. Sometimes that’s what we do to express ourselves, but we have to understand the consequences of the conversational tools we use and where they’re appropriate. That’s part of emotional and intellectual maturity. And this isn’t about being perfect in your engagement - we all have our moments and step a little too far, but when one displays a pattern of consistent misrepresentation, we now have an issue. That is a person who does not subscribe to the fundamental premise of the community, and believes that it should be proceeding from a different premise.
A simple example of common problematic bad-faith engagement is playing the devil’s advocate. I know for a fact that almost everyone on this forum is guilty of doing so from time to time, and it’s worth it to interrogate why it is you feel the need to present an argument to which you do not subscribe. What purpose does this serve? What are you trying to accomplish? Could you accomplish this in another way? Someone who persistently advocates for the devil is obfuscating their personality and motives. It creates distrust in a space that is ostensibly about building trust, and when it becomes a pattern it means the person doing so is trying to sow distrust and discord.
Persistent off-topic commentary can also be a common method of bad-faith engagment. Up above, Ikatano displays this flagrantly. This is a discussion about a code of conduct, and within that code of conduct we got an off-topic comment about calling for “unity.” This is a fine conversation point - for a different discussion. Why then, in a topic about something else, would you bring up an unrelated point? Further down, the answer is laid bare: the poster has another motive that they are bringing to this discussion. The off-topic comment reveals that they don’t care about the topic at hand - they want to talk about something else they think is more important, in this case a continuation of political discussion into a topic that is not about that.
The problem is that doing so in an unrelated topic dismisses the importance of that topic to others. The persistent off-topic bad-faith poster is saying that the opinions of others are unimportant to them, and that we should be talking about the thing they think is important. A community is a give-and-take exchange, but that type of bad-faith engagement demonstrates that the person is uninterested in giving up any part of their ego to the community.
Emotional maturation comes as you realize that a community is not all about you nor is it about your pet issues. Different people are motivated by different things and come to different conclusions, and not only is that okay, that’s actually a good thing. It means that if you engage in good faith, you will be exposed to ideas that you may not have otherwise had that can give you insight into your own journey. When you proceed with disingenuous arguments, you are saying that you are done growing, that you are right and don’t need to hear other perspectives, and that others are wrong and should come over to you. Does that sound like an attempt at building community? No, it doesn’t. It sounds like an attempt at dictating community, which is an inherently flawed premise.
So the tl;dr is that defining “bad faith” is pointless. Instead, focus on “good faith” by honestly representing yourself and what you believe in a discussion, instead of bringing in unrelated points that betray your motivation.