I see icons to the left of threads in the forum, of different kinds of envelopes. I don't know what those are. Where's the explanation for these icons? I'm not talking about icons the user entered, such as the emoticons.
The dark envelope means you've read the thread, a red one with an yellow arrow means the thread has been moved, an envelope on fire means the thread is popular (has been viewed many times), an envelope with a lock icon means the thread is closed and an envelope with a green circle and a white arrow means you've posted in the thread.