For upgraders, patch-pl-tl-il-unique-index.sql has added these three UNIQUE indeces to the scheme:
- il_to
- pl_namespace
- tl_namespace
For new installations, maintenance/tables.sql in contrast only contains normal (non-unique) indeces here.
Adjust either the one or the other!
I guess it would be correct to fix tables.sql to have the indeces UNIQUE also for new installations.