@Override
		public void run() {
			boolean animateBackground =
				useAnimations && (!waitingList.isEmpty() || !runningList.isEmpty());
			TaskInfo element = new TaskInfo(task, animateBackground);
			ListIterator<AbstractTaskInfo> listIterator = waitingList.listIterator();
			while (listIterator.hasNext()) {
				AbstractTaskInfo nextElement = listIterator.next();
				if (element.compareTo(nextElement) < 0) {
					listIterator.previous();
					listIterator.add(element);
					return;
				}
			}
			waitingList.addLast(element);
		}
Uses a layered pane to create a "watermark effect" to show when the GTaskManger is suspended.
Ghidra/Framework/Project/src/main/java/ghidra/framework/task/gui/taskview/TaskViewer.java