diff --git a/src/test/regress/expected/reindex_catalog.out b/src/test/regress/expected/reindex_catalog.out
index 142616fccbb..4b5fba49493 100644
--- a/src/test/regress/expected/reindex_catalog.out
+++ b/src/test/regress/expected/reindex_catalog.out
@@ -1,8 +1,8 @@
 --
 -- Check that system tables can be reindexed.
 --
--- Note that this test currently has to run without parallel tests
--- being scheduled, as currently reindex catalog tables can cause
+-- Note that this test currently is not included in the default
+-- schedules, as currently reindexing catalog tables can cause
 -- deadlocks:
 --
 -- * The lock upgrade between the ShareLock acquired for the reindex
@@ -16,6 +16,11 @@
 --   tables are routinely released before commit - therefore the lock
 --   held for reindexing doesn't guarantee that no running transaction
 --   performed modifications in the table underlying the index.
+--
+--   This is particularly problematic as such conflicts can be
+--   triggered even when run in isolation, as a previous session's
+--   temporary table cleanup might still be running (even when the
+--   session ended from a client perspective).
 -- Check reindexing of whole tables
 REINDEX TABLE pg_class; -- mapped, non-shared, critical
 REINDEX TABLE pg_index; -- non-mapped, non-shared, critical
diff --git a/src/test/regress/parallel_schedule b/src/test/regress/parallel_schedule
index cdbb08c7b3e..8112626f3bd 100644
--- a/src/test/regress/parallel_schedule
+++ b/src/test/regress/parallel_schedule
@@ -57,11 +57,6 @@ test: create_misc create_operator create_procedure
 # These depend on the above two
 test: create_index create_view index_including
 
-# ----------
-# Has to run in isolation, due to deadlock risk
-# ----------
-test: reindex_catalog
-
 # ----------
 # Another group of parallel tests
 # ----------
diff --git a/src/test/regress/serial_schedule b/src/test/regress/serial_schedule
index 7de53c617f8..b2a8f370563 100644
--- a/src/test/regress/serial_schedule
+++ b/src/test/regress/serial_schedule
@@ -67,7 +67,6 @@ test: create_procedure
 test: create_index
 test: index_including
 test: create_view
-test: reindex_catalog
 test: create_aggregate
 test: create_function_3
 test: create_cast
diff --git a/src/test/regress/sql/reindex_catalog.sql b/src/test/regress/sql/reindex_catalog.sql
index 2180ee5791a..87ecf52244f 100644
--- a/src/test/regress/sql/reindex_catalog.sql
+++ b/src/test/regress/sql/reindex_catalog.sql
@@ -1,8 +1,8 @@
 --
 -- Check that system tables can be reindexed.
 --
--- Note that this test currently has to run without parallel tests
--- being scheduled, as currently reindex catalog tables can cause
+-- Note that this test currently is not included in the default
+-- schedules, as currently reindexing catalog tables can cause
 -- deadlocks:
 --
 -- * The lock upgrade between the ShareLock acquired for the reindex
@@ -16,6 +16,11 @@
 --   tables are routinely released before commit - therefore the lock
 --   held for reindexing doesn't guarantee that no running transaction
 --   performed modifications in the table underlying the index.
+--
+--   This is particularly problematic as such conflicts can be
+--   triggered even when run in isolation, as a previous session's
+--   temporary table cleanup might still be running (even when the
+--   session ended from a client perspective).
 
 
 -- Check reindexing of whole tables