Currently the row's opacity is changed from 0% to 100% depending on focus state, but it
does not actually become hidden when at 0% opacity. This means that it's possible to
click the invisible buttons accidentally when focusing the applet. This has been an
issue for a long time, but becomes dangerous with D28064, since you could delete a note
just by clicking in the bottom-right corner to focus the applet!
This patch makes the button row actually hidden when the applet is not focused, not just