diff -U3 /home/postgres/postgres/src/test/regress/expected/constraints.out /home/postgres/postgres/build/testrun/pg_upgrade/002_pg_upgrade/data/results/constraints.out
--- /home/postgres/postgres/src/test/regress/expected/constraints.out	2026-03-19 10:20:09.440231702 +0000
+++ /home/postgres/postgres/build/testrun/pg_upgrade/002_pg_upgrade/data/results/constraints.out	2026-03-19 10:21:55.148523458 +0000
@@ -1127,8 +1127,10 @@
 INSERT INTO ne_nn_tbl VALUES (NULL); -- ok
 ALTER TABLE ne_nn_tbl ALTER CONSTRAINT nn ENFORCED; -- error
 ERROR:  cannot alter enforceability of constraint "nn" of relation "ne_nn_tbl"
+HINT:  Only foreign key and check constraints can change enforceability.
 ALTER TABLE ne_nn_tbl ALTER CONSTRAINT nn NOT ENFORCED; -- error
 ERROR:  cannot alter enforceability of constraint "nn" of relation "ne_nn_tbl"
+HINT:  Only foreign key and check constraints can change enforceability.
 ALTER TABLE ne_nn_tbl VALIDATE CONSTRAINT nn; -- error
 ERROR:  cannot validate NOT ENFORCED constraint
 ALTER TABLE ne_nn_tbl ADD CONSTRAINT nn_enforced1 NOT NULL x NOT ENFORCED;  -- error