diff --git a/test_runner/fixtures/neon_fixtures.py b/test_runner/fixtures/neon_fixtures.py
index b7afbec403..469bc8a1e5 100644
--- a/test_runner/fixtures/neon_fixtures.py
+++ b/test_runner/fixtures/neon_fixtures.py
@@ -4988,8 +4988,13 @@ def check_restored_datadir_content(
 
     restored_files = list_files_to_compare(restored_dir_path)
 
+    # pg_notify files are always ignored
+    pgdata_files = [f for f in pgdata_files if not f.startswith("pg_notify")]
+    restored_files = [f for f in restored_files if not f.startswith("pg_notify")]
+
+    # pg_xact and pg_multixact files are optional in basebackup: depending on our configuration they
+    # may be omitted and loaded on demand.
     if pgdata_files != restored_files:
-        # filter pg_xact and multixact files which are downloaded on demand
         pgdata_files = [
             f
             for f in pgdata_files
diff --git a/test_runner/regress/test_pg_regress.py b/test_runner/regress/test_pg_regress.py
index c5ae669dce..411888efbc 100644
--- a/test_runner/regress/test_pg_regress.py
+++ b/test_runner/regress/test_pg_regress.py
@@ -261,7 +261,7 @@ def test_isolation(
         pg_bin.run(pg_isolation_regress_command, env=env_vars, cwd=runpath)
 
     # This fails with a mismatch on `pg_multixact/offsets/0000`
-    # post_checks(env, test_output_dir, DBNAME, endpoint)
+    post_checks(env, test_output_dir, DBNAME, endpoint)
 
 
 # Run extra Neon-specific pg_regress-based tests. The tests and their