Blynk local server V3 certificates

When creating V1 ssl certificates, Blynk server works OK, but with a V3 certificate, the error is given:
Error initializing ssl context. Reason : File does not contain valid certificates:

However, file has a certificate perfectly readable with openssl and generated in the same way as V1, except to include some V3 extensions.

I need V3 certificate, because server has different names and different IPs to the outside and inside world. The certificate is signed with a CA (not a self-signed certificate).

Does anyone have a V3 certificate working with Blynk server?