diff --git a/java/com/google/gerrit/server/git/MergeUtil.java b/java/com/google/gerrit/server/git/MergeUtil.java
index 4088c81db8..e464e818c2 100644
--- a/java/com/google/gerrit/server/git/MergeUtil.java
+++ b/java/com/google/gerrit/server/git/MergeUtil.java
@@ -17,15 +17,17 @@ package com.google.gerrit.server.git;
 import static com.google.common.base.Preconditions.checkArgument;
 import static com.google.common.base.Preconditions.checkState;
 import static com.google.common.collect.ImmutableSet.toImmutableSet;
+import static com.google.common.collect.ImmutableSortedSet.toImmutableSortedSet;
 import static com.google.gerrit.git.ObjectIds.abbreviateName;
 import static java.nio.charset.StandardCharsets.UTF_8;
+import static java.util.Comparator.naturalOrder;
 import static java.util.Objects.requireNonNull;
+import static java.util.stream.Collectors.joining;
 
-import com.google.common.base.Joiner;
 import com.google.common.base.Strings;
-import com.google.common.collect.FluentIterable;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableSet;
+import com.google.common.collect.ImmutableSortedSet;
 import com.google.common.collect.Iterables;
 import com.google.common.collect.Sets;
 import com.google.common.flogger.FluentLogger;
@@ -68,7 +70,6 @@ import java.util.Collection;
 import java.util.Collections;
 import java.util.HashMap;
 import java.util.Iterator;
-import java.util.LinkedHashSet;
 import java.util.List;
 import java.util.Map;
 import java.util.Objects;
@@ -847,26 +848,22 @@ public class MergeUtil {
       return String.format("Merge \"%s\"", c.getShortMessage());
     }
 
-    LinkedHashSet<String> topics = new LinkedHashSet<>(4);
-    for (CodeReviewCommit c : merged) {
-      if (!Strings.isNullOrEmpty(c.change().getTopic())) {
-        topics.add(c.change().getTopic());
-      }
-    }
+    ImmutableSortedSet<String> topics =
+        merged.stream()
+            .map(c -> c.change().getTopic())
+            .filter(t -> !Strings.isNullOrEmpty(t))
+            .map(t -> "\"" + t + "\"")
+            .collect(toImmutableSortedSet(naturalOrder()));
 
-    if (topics.size() == 1) {
-      return String.format("Merge changes from topic \"%s\"", Iterables.getFirst(topics, null));
-    } else if (topics.size() > 1) {
-      return String.format("Merge changes from topics \"%s\"", Joiner.on("\", \"").join(topics));
-    } else {
+    if (!topics.isEmpty()) {
       return String.format(
-          "Merge changes %s%s",
-          FluentIterable.from(merged)
-              .limit(5)
-              .transform(c -> c.change().getKey().abbreviate())
-              .join(Joiner.on(',')),
-          merged.size() > 5 ? ", ..." : "");
+          "Merge changes from topic%s %s",
+          topics.size() > 1 ? "s" : "", topics.stream().collect(joining(", ")));
     }
+    return merged.stream()
+        .limit(5)
+        .map(c -> c.change().getKey().abbreviate())
+        .collect(joining(",", "Merge changes ", merged.size() > 5 ? ", ..." : ""));
   }
 
   public ThreeWayMerger newThreeWayMerger(ObjectInserter inserter, Config repoConfig) {
diff --git a/javatests/com/google/gerrit/acceptance/rest/change/AbstractSubmit.java b/javatests/com/google/gerrit/acceptance/rest/change/AbstractSubmit.java
index f3c61ca82d..c2df9cac34 100644
--- a/javatests/com/google/gerrit/acceptance/rest/change/AbstractSubmit.java
+++ b/javatests/com/google/gerrit/acceptance/rest/change/AbstractSubmit.java
@@ -506,10 +506,10 @@ public abstract class AbstractSubmit extends AbstractDaemonTest {
     assume().that(isSubmitWholeTopicEnabled()).isTrue();
     String topic1 = "test-topic-1";
     String topic2 = "test-topic-2";
-    PushOneCommit.Result change1 = createChange("Change 1", "a.txt", "content", topic2);
-    PushOneCommit.Result change2 = createChange("Change 2", "b.txt", "content", topic2);
-    PushOneCommit.Result change3 = createChange("Change 3", "c.txt", "content", topic1);
-    PushOneCommit.Result change4 = createChange("Change 4", "d.txt", "content", topic1);
+    PushOneCommit.Result change1 = createChange("Change 1", "a.txt", "content", topic1);
+    PushOneCommit.Result change2 = createChange("Change 2", "b.txt", "content", topic1);
+    PushOneCommit.Result change3 = createChange("Change 3", "c.txt", "content", topic2);
+    PushOneCommit.Result change4 = createChange("Change 4", "d.txt", "content", topic2);
     approve(change1.getChangeId());
     approve(change2.getChangeId());
     approve(change3.getChangeId());
@@ -518,12 +518,12 @@ public abstract class AbstractSubmit extends AbstractDaemonTest {
     String expectedTopic1 = name(topic1);
     String expectedTopic2 = name(topic2);
     if (getSubmitType() == SubmitType.CHERRY_PICK) {
-      change1.assertChange(Change.Status.NEW, expectedTopic2, admin);
-      change2.assertChange(Change.Status.NEW, expectedTopic2, admin);
+      change1.assertChange(Change.Status.NEW, expectedTopic1, admin);
+      change2.assertChange(Change.Status.NEW, expectedTopic1, admin);
 
     } else {
-      change1.assertChange(Change.Status.MERGED, expectedTopic2, admin);
-      change2.assertChange(Change.Status.MERGED, expectedTopic2, admin);
+      change1.assertChange(Change.Status.MERGED, expectedTopic1, admin);
+      change2.assertChange(Change.Status.MERGED, expectedTopic1, admin);
     }
 
     // Check for the exact change to have the correct submitter.