EasyRSA-3.2.1: easyrsa export-p12 with usefn is not working

[zappee]

I am using EasyRSA-3.1.7 and the following command works like a charm:

./easyrsa \
    --passin="pass:$EASYRSA_PASS" \
    --passout="pass:$EASYRSA_PASS" \
    export-p12 "$domain" usefn

After upgrade to EasyRSA-3.2.1 my scripts are failing with this error:

Unknown command option: 'usefn'

The easyrsa help export-p12 shows me the supported commands but usefn is not there. So I removed usefn from the end of my command but now applications are complaining about a wrong certificate:

tls: failed to verify certificate: x509: certificate relies on legacy Common Name field, use SANs instead

Unfortunately I could not found any EasyRSA migration document or any info about this change. What is the alternative way to use the usefn with the latest release?

Thanks.