Comment 2 for bug 1876831

So, it works without a custom udev rule in 19.10, but does not work without a custom udev rule in 20.04? Just want to confirm my understanding.

Can you paste the output of these commands, from both your 19.10 and 20.04 systems? Run them while you have the 'micro:bit' device connected, of course, and also please remove any custom udev rule(s) you have added and reboot.

$ lsusb -t
$ find /dev/bus/usb -ls