After the upgrade to Thunderbird 78.1.0 (from 68) [on Windows 8.1] there are two addressbooks with an empty title.

I am not sure if I had those in 68 or if these are the results of automatic imports of some kind of addressbook files. (Unfortunately, while reproducing a different issue, I also launched the backup with 78 and cannot check this anymore).

Interesting. Could you post a copy of all the prefs beginning with ldap_2.servers., or just the ones relevant to the untitled books?

Comparing the content of abook-<number>.mab.bak with what the contacts listed in the addressbooks by Thunderbird 78 shows contacts are missing. One of the the affected addressbooks has the name ldap_2.servers.Freunde_1.filename. The same pattern applies to the other addressbook and no other addressbooks: It has a _2 at the end of the pref name left of .filename. Both might also be the oldest addressbooks (potentially going back to Thunderbird 0.3).

(In reply to Sebastian Hengst [:aryx] (needinfo on intermittent or backout) from comment #0)

I am not sure if I had those in 68 or if these are the results of automatic imports of some kind of addressbook files. (Unfortunately, while reproducing a different issue, I also launched the backup with 78 and cannot check this anymore).

Are you saying you no longer have the .bak files for the address books?

Geoff, any suggestions based on comment 2

I'm confused. Are we still talking about missing titles from comment 0 or missing contacts from comment 2? Either way I don't really have anything to add.

(In reply to Geoff Lankow (:darktrojan) from comment #5)

I'm confused. Are we still talking about missing titles from comment 0 or missing contacts from comment 2? Either way I don't really have anything to add.

That's a question for Aryx.

Also, does the issue reproduce with 90.0b2 or newer, which has reimplemented ldap in JS?

Resolved per whiteboard