When Clients.showNotification is called with not null component reference, there is chance that after resize of window, the position of notification popup is wrong. (screenshot1)

If component is visible after resize, popup has good position. (screenshot2)
If component is not in the viewport, popups position is wrong. (screenshot3)

Clients.showNotification(message, Clients.NOTIFICATION_TYPE_ERROR, component, "before_end", 0);