You can try this: libreelec-generic.x86_64-9.0-devel-20180713105447-32ef9ba-certs-test.img.gz
- remove mount line of /etc/ssl from autostart.sh
- create folder /storage/.config/ssl-certs if doesn't exist
- copy your cacert.pem file there (filename is not important)
- update certs with command update-ca-certificates.sh