diff --git a/builtin/fmt-merge-msg.c b/builtin/fmt-merge-msg.c
index 1bc6b8b8c..c90f6d685 100644
--- a/builtin/fmt-merge-msg.c
+++ b/builtin/fmt-merge-msg.c
@@ -243,10 +243,10 @@ static void credit_people(struct strbuf *out,
 	const char *me;
 
 	if (kind == 'a') {
-		label = "\nBy ";
+		label = "\n# By ";
 		me = git_author_info(IDENT_NO_DATE);
 	} else {
-		label = "\nvia ";
+		label = "\n# Via ";
 		me = git_committer_info(IDENT_NO_DATE);
 	}
 
diff --git a/t/t6200-fmt-merge-msg.sh b/t/t6200-fmt-merge-msg.sh
index 9b50f54cc..992c2a046 100755
--- a/t/t6200-fmt-merge-msg.sh
+++ b/t/t6200-fmt-merge-msg.sh
@@ -102,8 +102,8 @@ test_expect_success '[merge] summary/log configuration' '
 	cat >expected <<-EOF &&
 	Merge branch ${apos}left${apos}
 
-	By Another Author (3) and A U Thor (2)
-	via Another Committer
+	# By Another Author (3) and A U Thor (2)
+	# Via Another Committer
 	* left:
 	  Left #5
 	  Left #4
@@ -149,8 +149,8 @@ test_expect_success 'merge.log=3 limits shortlog length' '
 	cat >expected <<-EOF &&
 	Merge branch ${apos}left${apos}
 
-	By Another Author (3) and A U Thor (2)
-	via Another Committer
+	# By Another Author (3) and A U Thor (2)
+	# Via Another Committer
 	* left: (5 commits)
 	  Left #5
 	  Left #4
@@ -166,8 +166,8 @@ test_expect_success 'merge.log=5 shows all 5 commits' '
 	cat >expected <<-EOF &&
 	Merge branch ${apos}left${apos}
 
-	By Another Author (3) and A U Thor (2)
-	via Another Committer
+	# By Another Author (3) and A U Thor (2)
+	# Via Another Committer
 	* left:
 	  Left #5
 	  Left #4
@@ -190,8 +190,8 @@ test_expect_success '--log=3 limits shortlog length' '
 	cat >expected <<-EOF &&
 	Merge branch ${apos}left${apos}
 
-	By Another Author (3) and A U Thor (2)
-	via Another Committer
+	# By Another Author (3) and A U Thor (2)
+	# Via Another Committer
 	* left: (5 commits)
 	  Left #5
 	  Left #4
@@ -207,8 +207,8 @@ test_expect_success '--log=5 shows all 5 commits' '
 	cat >expected <<-EOF &&
 	Merge branch ${apos}left${apos}
 
-	By Another Author (3) and A U Thor (2)
-	via Another Committer
+	# By Another Author (3) and A U Thor (2)
+	# Via Another Committer
 	* left:
 	  Left #5
 	  Left #4
@@ -238,8 +238,8 @@ test_expect_success 'fmt-merge-msg -m' '
 	cat >expected.log <<-EOF &&
 	Sync with left
 
-	By Another Author (3) and A U Thor (2)
-	via Another Committer
+	# By Another Author (3) and A U Thor (2)
+	# Via Another Committer
 	* ${apos}left${apos} of $(pwd):
 	  Left #5
 	  Left #4
@@ -271,8 +271,8 @@ test_expect_success 'setup: expected shortlog for two branches' '
 	cat >expected <<-EOF
 	Merge branches ${apos}left${apos} and ${apos}right${apos}
 
-	By Another Author (3) and A U Thor (2)
-	via Another Committer
+	# By Another Author (3) and A U Thor (2)
+	# Via Another Committer
 	* left:
 	  Left #5
 	  Left #4
@@ -396,8 +396,8 @@ test_expect_success 'merge-msg two tags' '
 	  Common #2
 	  Common #1
 
-	By Another Author (3) and A U Thor (2)
-	via Another Committer
+	# By Another Author (3) and A U Thor (2)
+	# Via Another Committer
 	* tag ${apos}tag-l5${apos}:
 	  Left #5
 	  Left #4
@@ -426,8 +426,8 @@ test_expect_success 'merge-msg tag and branch' '
 	  Common #2
 	  Common #1
 
-	By Another Author (3) and A U Thor (2)
-	via Another Committer
+	# By Another Author (3) and A U Thor (2)
+	# Via Another Committer
 	* left:
 	  Left #5
 	  Left #4