Hello!
The patch is simple and it does what it says it does, I verified the
difference in behavior with/without it.
I think the test case included in the email should be part of the
patch, maybe as a new file contrib/pg_trgm/sql/pg_trgm_collation.sql?
It also needs a proper commit message, and seems like the affected
indexes will need a REINDEX after this fix.
