Today a ran into a problem. OpenSuSE 15.3 fully updated, I rebooted the system due to new kernel update.

NetworkManager did not show any WiFi Adapters. I tested around with Modemmanager, other USB WiFi-Adapter, nothing worked.
The Adapter was shown in lsusb, but ModemManager did not show up anything.
First I thought that is is related to kernel, udev or dbus, but that is not the case

After hours of research, I found the solution here:

Results that the latest update activated that unsupported modules (not flagged as supported by SuSE), will not be loaded unless
you allow unsupported modules.

You may test journalctl -f, the plug in the Adapter, and look again. If it tells you that there is an unsupported module, the above link does the work.
set 'allow_unsupported_modules 1' in /etc/modprobe.d/unsupported-modules

After that change, NetworkManager could see the adapter and everything works again.