Hovering above the Jami icon on the left bottom of the screen and the clicking the close (red 6) reduces the number 3 shown on the Jami icon on the left bottom of the screen. This indicates that a Jami instance has been closed.
However on the right bottom of the screen, the system panel still shows that 4 Jami programs are open (red 7). There should only be 3 Jami programs in the system tray on the bottom as 1 Jami program has been closed/quitted.