Market Window

When you scroll to a price that is far enough from the current market value that the current market value would normally scroll off the screen, DOMTrader displays the Market Window above or below the selected price. Every time the current market price changes, the Market Window re-centers the market price row so it is always in the middle of this window. You cannot place orders in this portion of the DOMTrader window, but you can click a price cell in the Market window to immediately jump to that price, and close the Market Window.

The small square in the lower left corner indicates that you have a limit order below the current price displayed.  Clicking the square moves the DOMTrader view, so that these orders can be seen.