Loading LDAP contacts fail (due to conversion?)

I cannot make it work on Nextcloud 23.0.2 and LDAP Contacts Backend 1.2.0

As far as I know, I configured the backend's addressbook correctly.
However, loading contacts from LDAP fails, and it fails so hard that it brings down global contact search in its entirety.

I never did php, but last time I managed to insert some printing to the affected code path, and I am pretty sure the configured search returns entries. Problem seems to be around LdapEntryToVcard Here is the sanitized log.

Feb 18 11:36:34 mail.example.com nextcloud[22355]: {"reqId":"64xjcQrCsrwtaqAncJzw","level":3,"time":"2022-02-18T10:36:34+00:00","remoteAddr":"86.59.192.114","user":"userName","app":"index","method":"POST","url":"/contactsmenu/contacts","message":"{\"Exception\":\"RuntimeException\",\"Message\":\"Invalid record or configuration for vcard\",\"Code\":0,\"Trace\":[{\"file\":\"nextcloud_full_path/apps/ldap_contacts_backend/lib/Service/LdapCardBackend.php\",\"line\":83,\"function\":\"convert\",\"class\":\"OCA\\\\LDAPContactsBackend\\\\Service\\\\LdapEntryToVcard\",\"type\":\"::\"},{\"file\":\"nextcloud_full_path/apps/ldap_contacts_backend/lib/Service/LdapCardBackend.php\",\"line\":64,\"function\":\"entryToCard\",\"class\":\"OCA\\\\LDAPContactsBackend\\\\Service\\\\LdapCardBackend\",\"type\":\"->\"},{\"file\":\"nextcloud_full_path/apps/ldap_contacts_backend/lib/Service/ContactsAddressBook.php\",\"line\":84,\"function\":\"searchCards\",\"class\":\"OCA\\\\LDAPContactsBackend\\\\Service\\\\LdapCardBackend\",\"type\":\"->\"},{\"file\":\"nextcloud_full_path/lib/private/ContactsManager.php\",\"line\":73,\"function\":\"search\",\"class\":\"OCA\\\\LDAPContactsBackend\\\\Service\\\\ContactsAddressBook\",\"type\":\"->\"},{\"file\":\"nextcloud_full_path/lib/private/Contacts/ContactsMenu/ContactsStore.php\",\"line\":111,\"function\":\"search\",\"class\":\"OC\\\\ContactsManager\",\"type\":\"->\"},{\"file\":\"nextcloud_full_path/lib/private/Contacts/ContactsMenu/Manager.php\",\"line\":70,\"function\":\"getContacts\",\"class\":\"OC\\\\Contacts\\\\ContactsMenu\\\\ContactsStore\",\"type\":\"->\"},{\"file\":\"nextcloud_full_path/core/Controller/ContactsMenuController.php\",\"line\":60,\"function\":\"getEntries\",\"class\":\"OC\\\\Contacts\\\\ContactsMenu\\\\Manager\",\"type\":\"->\"},{\"file\":\"nextcloud_full_path/lib/private/AppFramework/Http/Dispatcher.php\",\"line\":217,\"function\":\"index\",\"class\":\"OC\\\\Core\\\\Controller\\\\ContactsMenuController\",\"type\":\"->\"},{\"file\":\"nextcloud_full_path/lib/private/AppFramework/Http/Dispatcher.php\",\"line\":126,\"function\":\"executeController\",\"class\":\"OC\\\\AppFramework\\\\Http\\\\Dispatcher\",\"type\":\"->\"},{\"file\":\"nextcloud_full_path/lib/private/AppFramework/App.php\",\"line\":157,\"function\":\"dispatch\",\"class\":\"OC\\\\AppFramework\\\\Http\\\\Dispatcher\",\"type\":\"->\"},{\"file\":\"nextcloud_full_path/lib/private/Route/Router.php\",\"line\":302,\"function\":\"main\",\"class\":\"OC\\\\AppFramework\\\\App\",\"type\":\"::\"},{\"file\":\"nextcloud_full_path/lib/base.php\",\"line\":1006,\"function\":\"match\",\"class\":\"OC\\\\Route\\\\Router\",\"type\":\"->\"},{\"file\":\"nextcloud_full_path/index.php\",\"line\":36,\"function\":\"handleRequest\",\"class\":\"OC\",\"type\":\"::\"}],\"File\":\"nextcloud_full_path/apps/ldap_contacts_backend/lib/Service/LdapEntryToVcard.php\",\"Line\":65,\"CustomMessage\":\"--\"}","userAgent"...}

Start with apps/ldap_contacts_backend/lib/Service/LdapEntryToVcard.php at line 65 and trace how LdapCardBackend.php handles conversion at lines 64 and 83. Reproduce the POST to /contactsmenu/contacts with the reported Nextcloud and backend versions, then verify that LDAP contact loading no longer raises the vCard exception or disables global contact search.