Drag and Drop a Position Adding or Decreasing the Volume.

A feature that allows you to drag the position towards or away from the price adding or decreasing the volume.

Just like you can move a pending order to your desired price you should be able to move positions as well, and obviously if you are dragging it towards the current price it will add volume to it and if you are dragging away from current price it should decrease the volume from it.

This feature should work it it does on doubling the position's volume but more precise as you know where to place it.