But how can we know who to not speak to? They also claim there's no way to tell if someone is trans just by looking at them.

No, it's pretty easy to tell people like this. Just look for the type of person who has such an over-inflated sense of self-esteem they not only believe they're the main character , but that this is so self-evident that every person in the world also knows this and they are on everyone in the world's mind every second of every day.

Never forget: The reason they get mad if you use he/him or she/her, use they/them, or ask their pronouns, is because the troon cannot possibly fathom that you aren't obsessed with them enough to already KNOW what pronouns are on their Tumblr.