It is possible to debug any visualization. The only requirements is that the visualization you want to debug, must be running (meaning; the visualizations-COPP-program is executing.

Find the view you want to debug at the device where you have added the visualization, (or the visualization containing the visualization you want to debug (here you need to find the specific view you want to debug by clicking the + until you find it)), and then debug it, as you would do with a control component.