We use a derivative of Markdown. A couple of things are missing, and we've added a few of our own like two parentheses for ((invisible text))
Enter / return acts as you expect but if you hit it with ctrl, alt, meta, shift, or a double-tap, it'll send your message.
As much as possible, we try to make things work by magic. Drag an image into the conversation and it gets uploaded and embedded. Put in a link and it's converted to a hyperlink.
To set or change your nickname or your profile, just go to /me
We care about making things better. We can't guarantee we'll do everything you suggest but we'll try and if we don't, we have a good reason.