Hi. Maybe I have found a little bug in network config file. I use a self-build OpenWrt from master source on a Linksys WRT3200ACM (Rango).
Build configuration is standard for the device, but deselect the option for IPv6 support. When I deselect this option, the Globals section disappears in the "network" configuration file, which controls both "ula_prefix", which is related to IPv6, but also "packet_steering", which I want to activate and I believe is not connected to IPv6 in any way. Eventually I recreate the section manually and it also reappears in LuCI.
The expected behavior is that the Globals section remains with the only "packet_steering" option.