Have tried to cmd+o again, it warns me that an open ticket already exists for this trade.
Then I chose to open new ticket anyway, but nothing happens.
How to best get the attention of the arbitrator? The peer is out cold, probably thinks he got scammed, and there’s nothing I can do without the arbitrator stepping in.
I reopened and closed again. You should get the message. If not u might some corrupted data - please consider to switch to a new data directory as described here: How to switch to a new data directory