Additional drivers not working in 20.04.1

[MR ZenWiz]

I recently upgraded my desktop to Xubuntu 20.04.1 (actually,
reinstalled - see my other thread on this).

The Additional Drivers setting app does not appear to work.  I get no
response when I click in the /usr/bin/xfce4-settings-manager window or
use the mouse button to run Settings -> Additional Drivers.  I do get
an error window announcing an Ubuntu internal error, which I sent
upstream.

Has anyone seen this and found a way around it?

Thanks.

Mark