diff --git a/contrib/btree_gin/expected/bool.out b/contrib/btree_gin/expected/bool.out
index efb3e1e327..207a3f2328 100644
--- a/contrib/btree_gin/expected/bool.out
+++ b/contrib/btree_gin/expected/bool.out
@@ -87,13 +87,15 @@ EXPLAIN (COSTS OFF) SELECT * FROM test_bool WHERE i<=true ORDER BY i;
 (6 rows)
 
 EXPLAIN (COSTS OFF) SELECT * FROM test_bool WHERE i=true ORDER BY i;
-         QUERY PLAN          
------------------------------
+                QUERY PLAN                 
+-------------------------------------------
  Sort
    Sort Key: i
-   ->  Seq Scan on test_bool
+   ->  Bitmap Heap Scan on test_bool
          Filter: i
-(4 rows)
+         ->  Bitmap Index Scan on idx_bool
+               Index Cond: (i = true)
+(6 rows)
 
 EXPLAIN (COSTS OFF) SELECT * FROM test_bool WHERE i>=true ORDER BY i;
                 QUERY PLAN                 
diff --git a/contrib/btree_gist/expected/bool.out b/contrib/btree_gist/expected/bool.out
index c67a9685d5..29390f079c 100644
--- a/contrib/btree_gist/expected/bool.out
+++ b/contrib/btree_gist/expected/bool.out
@@ -71,7 +71,7 @@ SELECT * FROM booltmp WHERE a;
                 QUERY PLAN                
 ------------------------------------------
  Index Only Scan using boolidx on booltmp
-   Filter: a
+   Index Cond: (a = true)
 (2 rows)
 
 SELECT * FROM booltmp WHERE a;
@@ -85,7 +85,7 @@ SELECT * FROM booltmp WHERE NOT a;
                 QUERY PLAN                
 ------------------------------------------
  Index Only Scan using boolidx on booltmp
-   Filter: (NOT a)
+   Index Cond: (a = false)
 (2 rows)
 
 SELECT * FROM booltmp WHERE NOT a;
diff --git a/src/backend/optimizer/path/indxpath.c b/src/backend/optimizer/path/indxpath.c
index 045ff2e487..63a8eef45c 100644
--- a/src/backend/optimizer/path/indxpath.c
+++ b/src/backend/optimizer/path/indxpath.c
@@ -153,6 +153,7 @@ static IndexClause *match_clause_to_indexcol(PlannerInfo *root,
 											 RestrictInfo *rinfo,
 											 int indexcol,
 											 IndexOptInfo *index);
+static bool IsBooleanOpfamily(Oid opfamily);
 static IndexClause *match_boolean_index_clause(PlannerInfo *root,
 											   RestrictInfo *rinfo,
 											   int indexcol, IndexOptInfo *index);
@@ -2342,6 +2343,23 @@ match_clause_to_indexcol(PlannerInfo *root,
 	return NULL;
 }
 
+/*
+ * IsBooleanOpfamily
+ *	  Detect whether an opfamily supports boolean equality as an operator.
+ *
+ * If the opfamily OID is in the range of built-in objects, we can rely
+ * on hard-wired knowledge of which built-in opfamilies support this.
+ * For extension opfamilies, there's no choice but to do a catcache lookup.
+ */
+static bool
+IsBooleanOpfamily(Oid opfamily)
+{
+	if (opfamily < FirstNormalObjectId)
+		return IsBuiltinBooleanOpfamily(opfamily);
+	else
+		return op_in_opfamily(BooleanEqualOperator, opfamily);
+}
+
 /*
  * match_boolean_index_clause
  *	  Recognize restriction clauses that can be matched to a boolean index.
diff --git a/src/backend/optimizer/path/pathkeys.c b/src/backend/optimizer/path/pathkeys.c
index 1fa7fc99b5..b9c1ce0a64 100644
--- a/src/backend/optimizer/path/pathkeys.c
+++ b/src/backend/optimizer/path/pathkeys.c
@@ -1191,8 +1191,13 @@ partkey_is_bool_constant_for_query(RelOptInfo *partrel, int partkeycol)
 	PartitionScheme partscheme = partrel->part_scheme;
 	ListCell   *lc;
 
-	/* If the partkey isn't boolean, we can't possibly get a match */
-	if (!IsBooleanOpfamily(partscheme->partopfamily[partkeycol]))
+	/*
+	 * If the partkey isn't boolean, we can't possibly get a match.
+	 *
+	 * Partitioning currently can only use built-in AMs, so checking for
+	 * built-in boolean opclasses is good enough.
+	 */
+	if (!IsBuiltinBooleanOpfamily(partscheme->partopfamily[partkeycol]))
 		return false;
 
 	/* Check each restriction clause for the partitioned rel */
diff --git a/src/backend/partitioning/partprune.c b/src/backend/partitioning/partprune.c
index bf9fe5b7aa..b5403149d7 100644
--- a/src/backend/partitioning/partprune.c
+++ b/src/backend/partitioning/partprune.c
@@ -3596,7 +3596,11 @@ match_boolean_partition_clause(Oid partopfamily, Expr *clause, Expr *partkey,
 
 	*outconst = NULL;
 
-	if (!IsBooleanOpfamily(partopfamily))
+	/*
+	 * Partitioning currently can only use built-in AMs, so checking for
+	 * built-in boolean opclasses is good enough.
+	 */
+	if (!IsBuiltinBooleanOpfamily(partopfamily))
 		return PARTCLAUSE_UNSUPPORTED;
 
 	if (IsA(clause, BooleanTest))
diff --git a/src/include/catalog/pg_opfamily.h b/src/include/catalog/pg_opfamily.h
index 8dc9ce01bb..b56d714322 100644
--- a/src/include/catalog/pg_opfamily.h
+++ b/src/include/catalog/pg_opfamily.h
@@ -55,7 +55,8 @@ DECLARE_UNIQUE_INDEX_PKEY(pg_opfamily_oid_index, 2755, OpfamilyOidIndexId, on pg
 
 #ifdef EXPOSE_TO_CLIENT_CODE
 
-#define IsBooleanOpfamily(opfamily) \
+/* This does not account for non-core opclasses that might accept boolean */
+#define IsBuiltinBooleanOpfamily(opfamily) \
 	((opfamily) == BOOL_BTREE_FAM_OID || (opfamily) == BOOL_HASH_FAM_OID)
 
 #endif							/* EXPOSE_TO_CLIENT_CODE */