Same Problem here. In 5.23 I cannot pair the 8bitdo to by USB Bluetooth Dongle. It worked in older releases, now I push on "connect bluetooth device" and immediately I get the message "device found" althought the controller is still in pairing mode and not connected. I think the XU4 just checks whether a dongle is connected and does not search for controllers.
Edit: Of course I did "forget all BT devices"