Comment 5 for bug 1999833

Logging out and in again should be enough. Although that wouldn't be true where the login screen (also hosted by gnome-shell) was still running during your desktop login but these days the login screen is stopped and restarted on demand. So indeed logging out and in again should be sufficient if you were running GNOME. Or do nothing at all if you're logged into KDE (providing the login screen's gnome-shell instance is not still running).

So you're right, but it can be complicated.