Hi,
I can confirm that openldap-2.4.39 still has in issue with this.
When connecting via TLS I tried to modify olcTLSVerifyClient from never to try with following ldif:
dn: cn=config changetype: modify replace: olcTLSVerifyClient olcTLSVerifyClient: try
this caused slapd to hang indefinetely.
I was able to successfully modify above when connecting without TLS.
I need to complete my current task but will set up a small proof of concept later on in my lab.
Greetings Christian