Yes, according to contact with Salt, bridging will come in the next update. At the moment, only port forwarding works. Everything else will come soon.

I bought a Planet XT-705A SFP+ media converter for 200chf on bar. But with Salt Fiber and Fritzbox it does not work yet. I need VLAN ID from Salt, once Salt told me that is 30 or 40 but that does not work, does anyone know the VLAN ID and if I need to use a username and password ? Merci,

Of course, you have to connect the FritzBox behind the SaltBox. That means from the Salt Box to the FritzBox and then from the FritzBox to the terminals.