Cannot use yubikey in qubes with sys-usb / external hdd qubesos install / external keyboard

so I have a mini-pc with qubesOS installed in an external usb ssd

I have also an external usb keyboard and mouse

I created the sys-usb qube manually and got locked out, I figured it out by adding the “rd.qubes.dom0_usb=xxx” parameters to grub boot.

I guess that tells to connect the usb port used by the keyboard to dom0 at boot…

Now I am trying to use my yubikey in a web browser in a qube but I have an error such as “denied u2f.register to sys-usb”

I have a sys-usb qubes installed and it can start but there is no device attached to it…

I have searched in the forum and documentation but I have a hard time figuring out what to do to let the u2f-proxy access to my yubikey via sys-usb…

Can someone advise or help ?