Hi! It seems that merging authorities with lots of linked biblios can lead to data corruption (at least in 21.05): The merging of the auth record itself seems to work, but the linking of the biblios from old to new auth record happens inside a normal synchrone web request. If this requests times out (because there might be a lot of biblio records to relink), some of the biblios still point to the old auth, which is already deleted. (At least this seems to be happening, based on the complaints we got from librarians) I guess the only fix is to handle authority merging via background jobs / job queue. Is this a known bug? I couldn't find anything about that in bugzilla? If yes, is there a timeframe when it will be fixed? If no, I will create a bug (though reproducing it will need some weird fixtures in the DB..). In any case, the Steiermärkische Landesbibliothek is keen to get this working, so I could give fixing it a try. But this will need some discussion, I assume? As I suppose this will be a bit more work than a single-line fix in a template, I'd like to have some backing by other Koha-devs, that this behaviour is indeed a bug, and that using background jobs is the correct way to fix it. Greetings, domm -- #!/usr/bin/perl https://domm.plix.at for(ref bless{},just'another'perl'hacker){s-:+-$"-g&&print$_.$/}