One more thing if you have already installed openwrt, you can install optional packages though luci but never upgrade already installed packages through opkg package manager to different version from inside luci, it can brick your router because opkg doesn't handle dependencies well.
I am not talking about openwrt firmware upgrade through sysupgrade option in luci but only about upgrading through package manager opkg.
I am not talking about openwrt firmware upgrade through sysupgrade option in luci but only about upgrading through package manager opkg.