<https://wiki.ubuntu.com/NotifyOSD#Outside%20the%20bubble>: "The first bubble on a display should be positioned 0.5 em from the bottom of whichever panels are at the top of the display (or 0.5 em from the top of the display, if it has no top panels)."
<https:/ /wiki.ubuntu. com/NotifyOSD# Outside% 20the%20bubble>: "The first bubble on a display should be positioned 0.5 em from the bottom of whichever panels are at the top of the display (or 0.5 em from the top of the display, if it has no top panels)."
So, the bubble in the screenshot is too low.