Per RFC3501 §6.3.1 and §6.3.2 ‘UIDNEXT’ must be returned in an OK
untagged response.  See also Appendix B#34.

However §6.3.1 suggests that it's in fact optional: “If this is missing,
the client can not make any assumptions about the next unique identifier
value.”

A correction was proposed in Errata ID 3445 https://www.rfc-editor.org/errata/eid3445 ,
and rejected on the ground that clients SHOULD support the implement
default behavior for missing data.

We heavily rely on the ‘UIDNEXT’ presence and won't implement a
workaround for its absence; instead we panic() with a more informative
message.

That's when get_version() was introduced.  Unfortunately the manual
doesn't mention it, but 1.85 is lacking the function, see

    https://github.com/radiator-software/p5-net-ssleay/blob/1.88/Changes#L216
    https://github.com/radiator-software/p5-net-ssleay/commit/ae33bb5405dadde973bc25a0c5e3941d5c83f8b1

Compatibility with Net::SSLeay 1.83 can be restored by reverting this
commit and 35f4ecefa9c9ff55acfdb337b215e3d13345c86d.

Also, clarify that SSL_cipherlist only applies to TLSv1.2 and below.
See SSL_CTX_set_cipher_list(3ssl).

It could in principle still work with earlier versions if the new
settings SSL_protocol_{min,max} are not used, however it's cumbersome to
do individual checks for specific settings, let alone maintain test
coverage with multiple OpenSSL versions.