diff -U3 /home/pgbfarm/buildroot/HEAD/pgsql.build/contrib/test_decoding/expected/twophase_snapshot.out /home/pgbfarm/buildroot/HEAD/pgsql.build/contrib/test_decoding/output_iso/results/twophase_snapshot.out
--- /home/pgbfarm/buildroot/HEAD/pgsql.build/contrib/test_decoding/expected/twophase_snapshot.out	2021-01-07 02:49:30.231809843 +0200
+++ /home/pgbfarm/buildroot/HEAD/pgsql.build/contrib/test_decoding/output_iso/results/twophase_snapshot.out	2021-01-09 04:01:26.730510078 +0200
@@ -26,6 +26,8 @@
 data           
 
 BEGIN          
+COMMIT         
+BEGIN          
 table public.do_write: INSERT: id[integer]:2
 COMMIT         
 step s2cp: COMMIT PREPARED 'test1';
@@ -33,6 +35,10 @@
 data           
 
 BEGIN          
+COMMIT         
+BEGIN          
+COMMIT         
+BEGIN          
 table public.do_write: INSERT: id[integer]:1
 PREPARE TRANSACTION 'test1'
 COMMIT PREPARED 'test1'