Tvheadend

Hi,

I am using the stable version, but I thought I'd give a try to 3.9.470 and this seems promising, however I got stucked with the IPTV streams.
In the stable version the IPTV tab is quite straight-forward, those are working, but in 3.9.470 I am not able to figure out how to input the IGMP groups.
Can someone give me a hint please?

Thanks,
Levente