[syslog-ng] Certificate valid, but invalid purpose

Running syslog-ng 3.22 OSE on Fedora 31 installation.  I am in the process of implementing TLS encryption on the remote links.  I have the links working, including the mutual authentication function.  However, I am getting the warning "Certificate valid, but purpose is invalid" on startup.  Since it is a warning, it does not seem to be affecting the functionality.   The certificates are self signed, with TLS Web Server Authentication and  TLS Web Client Authentication extensions, among others. I am unable to find any documentation defining what additional extensions are needed to silence this warning.  Can anyone tell me what additional is required?