Comment 4 for bug 333517

I think it would be valuable to have a help bubble mechanism that can point at or highlight particular interface elements (useful for guided tours, tutorials etc), but I don't think notification bubbles can be that mechanism. Queueing notification bubbles means that the relevant interface element is even more likely to have moved by the time the bubble appears. And when a confirmation bubble (volume, brightness, etc) is already on the screen, it's quite likely to be placed between any newer notification bubble and the thing it wants to point to. (notification-daemon blithely ignored this problem, which resulted in bubbles covering each other as they fought to point at different elements on the panel.)