Package luci-proto-relay

Hello everybody,
I'm new in the forum, I have a question about availability of luci-proto-relay package.
Is it still available or it's not parto of 19.0.

I compiled my own kernel excluding some modules as suggested to save space, adding kmod-trelay.

But when I configure network and wireless with uci set, I see LuCi warning me I need a protocol on the repeater_bridge interface (luci-proto-relay) that I'm not able to find anywhere.

An hint?
Thanks in advance

Linux OpenWrt 5.4.91
LuCI Master (git-21.023.26565-fb6e62e)](https://github.com/openwrt/luci)
OpenWrt SNAPSHOT r15595-29167cbca3