Comment # 1 on bug 1130277 from Maurizio Galli

(In reply to Robert Schweikert from comment #0)
> NAME="openSUSE Tumbleweed"
> VERSION_ID="20190320"
> 
> When clicking on the NetworkManager applet the available network connections
> are not shown. Previously when clicking on the applet in the panel a menu
> was shown that allowed the user to select a specific network to connect to.
> This no longer works.
> 
> Under "Network Settings" in YAsT "Network Manager" is selected. Same
> behavior occurs when "Wicked" is selected.
> 
> # ps -A | grep nm
>  4721 ?        00:00:05 nm-applet
> # ps -A | grep Network
>  7472 ?        00:00:01 NetworkManager
> 
> The effect is that the user cannot select a specific network to connect to.

Could you say if your panel is using Status Notifier Plugin or the older
systray aka "Notification Area" plugin?