In EasyEDA Pro, when I want to insert a node into a copper region, I select the region and then choose "Insert node" from the pop-up menu. A message appears saying, "Please select a node to insert." But where exactly am I supposed to click to insert the node? I click many times around the copper region, but nothing happens. Occasionally, after numerous attempts, the node is finally inserted. Most of the time, I give up in frustration without managing to insert the node.