When a notification pops up, clicking on it does nothing, meaning it stays there and obscures the system tray. Also, if you open the notifications, none of the ones listed have an X and cannot be dismissed. Also clicking on them does nothing, which it should take you somewhere depending on the notification.
Also, even though when you mouse over "Clear all notifications" it changes color, clicking it has no effect.
I suspect this is an artifact of not being able to dismiss the RU notification in the free version, but that is turned off and no such notification is appearing when logging in remotely.
This is with server - hey guess what, I can't tell you because there is a Dell notification I can't dismiss over the extra system tray icons so I cannot get to the RU one - and Viewer 18.104.22.168. Server system is Windows 10 Home 1809, viewer is Windows 10 Enterprise 1903. This happens on three different server systems, all laptops with discrete nVidia graphics. I do not experience this problem on desktops.