First, is there a way to insert line-breaks into a comment? This is often frustrating me because the comments are sometimes quite unreadable without line-breaks.
It would be also nice if [Enter] didn't submit the comment; this still surprises me sometimes and makes me add unfinished comment. (I don't believe it can be changed though).
More generally, is there some nice FAQ or other resource where one can learn everything about the site's user interface?