Just a quick fyi. A line of text has been added above the Surrender button to explain that clicking it will permanently remove you from the game. The Confirmation box when you click Surrender asking you to confirm you want to surrender is still in place, but it appears some people don't usually read these, so the line is an extra protection to make sure it is clear what Surrender means.
Hopefully this will help avoid more accidental surrenders, which can of course be very painful.