This fixes #14796 (on Buster, it is displayed in the middle of the screen, on
the left of the clock) and an annoying UX problem we have on Stretch:  OpenPGP
applet is in the middle of icons that share the exact same (modern, GNOME
Shell-like) behaviour, which is disturbing when opening one of the modern menus
and moving the mouse left/right to the others, because in the middle one icon
won't react as expected, and the nice blue bottom border continuity is broken.