I'm nit if that is the best solution, but it works for me.
I'm using LibreELEC on an Intel device and can't find the place where you can set the environment variables permanently. This is apparently not described in the entire wiki. I need it because I am using a firewall that also inspects SSL traffic.
I copied cacert.pem and attached my private ca certificate and pu it to
Code
mkdir -p /usr/share/kodi/system/certs/
cp /usr/share/kodi/system/certs/cacert.pem /storage/local/share/ca-certificates/cacert.pem
cat myPrivateCacert.pem >> /storage/local/share/ca-certificates/cacert.pem
My trick ist to use an own addon script to set the environment variable.