Rooms, like users, have simple names. If you name a room which doesn't exist, it'll be created. The person who creates the room is the owner of it.
There'll be a big startup circle welcoming you. Click it, and you should hear a little "online" sound.
are audio.
The indicator will be green if you haven't heard that message
yet, otherwise pink. Click the indicator, and it'll play.
Lines starting with a 
are text
messages. If it's too long, it'll end with ellipses. Click
on the text, and a viewing window will pop up to see the text
in its entirety.
centered.
When you click the red circle, a recording from your mic will start.
To the left, a counter appears, indicating your recording duration.
to the right, a 
cancel button appears.
Record your message. If you stumble and don't like your result, click the cancel. Otherwise click the progress bars which took the place of the red circle. Your audio will be uploaded and posted to the room. If there is text in the text input box, it will be included, as a label for your audio message.
send symbol) to post text to the room.
Because each audio message is its own entry, you can also click on one to hear it again.
Like Jitsi, Commoxy is open source