diff --git a/bots/mlbridge/src/main/java/org/openjdk/skara/bots/mlbridge/ArchiveWorkItem.java b/bots/mlbridge/src/main/java/org/openjdk/skara/bots/mlbridge/ArchiveWorkItem.java
index abc19832..a10cc7a8 100644
--- a/bots/mlbridge/src/main/java/org/openjdk/skara/bots/mlbridge/ArchiveWorkItem.java
+++ b/bots/mlbridge/src/main/java/org/openjdk/skara/bots/mlbridge/ArchiveWorkItem.java
@@ -33,9 +33,10 @@
 import java.nio.file.Path;
 import java.time.Duration;
 import java.util.*;
-import java.util.function.Consumer;
+import java.util.function.*;
 import java.util.logging.Logger;
 import java.util.regex.Pattern;
+import java.util.stream.Collectors;
 
 class ArchiveWorkItem implements WorkItem {
     private final PullRequest pr;
@@ -301,7 +302,16 @@ public void run(Path scratchPath) {
         pushMbox(archiveRepo, "Adding comments for PR " + bot.codeRepo().getName() + "/" + pr.getId());
 
         // Finally post all new mails to the actual list
-        newMails.forEach(list::post);
+        for (var newMail : newMails) {
+            var filteredHeaders = newMail.headers().stream()
+                                         .filter(header -> !header.startsWith("PR-"))
+                                         .collect(Collectors.toMap(Function.identity(),
+                                                                   newMail::headerValue));
+            var filteredEmail = Email.from(newMail)
+                                     .replaceHeaders(filteredHeaders)
+                                     .build();
+            list.post(filteredEmail);
+        }
     }
 
     @Override
diff --git a/bots/mlbridge/src/main/java/org/openjdk/skara/bots/mlbridge/ReviewArchive.java b/bots/mlbridge/src/main/java/org/openjdk/skara/bots/mlbridge/ReviewArchive.java
index 0ad00ba1..4c0e7d64 100644
--- a/bots/mlbridge/src/main/java/org/openjdk/skara/bots/mlbridge/ReviewArchive.java
+++ b/bots/mlbridge/src/main/java/org/openjdk/skara/bots/mlbridge/ReviewArchive.java
@@ -5,7 +5,6 @@
 import org.openjdk.skara.host.*;
 import org.openjdk.skara.vcs.Hash;
 
-import java.io.*;
 import java.net.URI;
 import java.nio.charset.StandardCharsets;
 import java.security.*;
@@ -184,12 +183,7 @@ void create(URI webrev) {
     }
 
     private String latestHeadPrefix() {
-        try {
-            var latestCommit = prInstance.localRepo().lookup(prInstance.headHash()).orElseThrow(RuntimeException::new);
-            return String.format("[Rev %02d]", revisionCount());
-        } catch (IOException e) {
-            throw new UncheckedIOException(e);
-        }
+        return String.format("[Rev %02d]", revisionCount());
     }
 
     void addFull(URI webrev) {
diff --git a/bots/mlbridge/src/test/java/org/openjdk/skara/bots/mlbridge/MailingListBridgeBotTests.java b/bots/mlbridge/src/test/java/org/openjdk/skara/bots/mlbridge/MailingListBridgeBotTests.java
index a9f28897..ddcd6fbb 100644
--- a/bots/mlbridge/src/test/java/org/openjdk/skara/bots/mlbridge/MailingListBridgeBotTests.java
+++ b/bots/mlbridge/src/test/java/org/openjdk/skara/bots/mlbridge/MailingListBridgeBotTests.java
@@ -881,6 +881,7 @@ void rebased(TestInfo testInfo) throws IOException {
             for (var newMail : conversations.get(0).allMessages()) {
                 assertEquals(noreplyAddress(archive), newMail.author().address());
                 assertEquals(sender, newMail.sender());
+                assertFalse(newMail.hasHeader("PR-Head-Hash"));
             }
             assertEquals("Re: [Rev 01]: RFR: This is a pull request", conversations.get(0).allMessages().get(1).subject());
         }
diff --git a/email/src/main/java/org/openjdk/skara/email/EmailBuilder.java b/email/src/main/java/org/openjdk/skara/email/EmailBuilder.java
index a1ebb7a0..6aa09e66 100644
--- a/email/src/main/java/org/openjdk/skara/email/EmailBuilder.java
+++ b/email/src/main/java/org/openjdk/skara/email/EmailBuilder.java
@@ -92,6 +92,12 @@ public EmailBuilder headers(Map<String, String> headers) {
         return this;
     }
 
+    public EmailBuilder replaceHeaders(Map<String, String> headers) {
+        this.headers.clear();
+        this.headers.putAll(headers);
+        return this;
+    }
+
     public EmailBuilder date(ZonedDateTime date) {
         this.date = date;
         return this;