On 19 Jul 2019, at 13.20, Dirk Koopman via dovecot <dovecot@dovecot.org> wrote:

But I am left with this:

Jul 19 14:09:52 localhost dovecot: indexer-worker: Error: User <someone> lookup failed: Couldn't load required plugin /usr/lib/dovecot/modules/lib90_sieve_plugin.so: dlopen() faile: /usr/lib/dovecot/modules/lib90_sieve_plugin.so: undefined symbol: mail_deliver_ctx_get_log_var_expand_table

Oh.. it's logged by indexer-worker.

mail_plugins = mail_log notify replication fts fts_lucene sieve

You can't load sieve globally. It needs to be inside protocol lmtp {}