@Override
			public void mouseClicked(MouseEvent e) {
				// when the user clicks the popup window, make sure that the outputTextField gets
				// the focus (so that the escape key and other hotkeys to manage the popup work
				// correctly
				outputTextField.requestFocusInWindow();
				/* double-click inserts a completion */
				if (e.getClickCount() == 2) {
					console.insertCompletion(getCompletion());
				}
			}
This class encapsulates a code completion popup Window for the ConsolePlugin.
Ghidra/Features/Base/src/main/java/ghidra/app/plugin/core/interpreter/CodeCompletionWindow.java