diff --git a/mercurial/bundle2.py b/mercurial/bundle2.py
index 4ee50d98d35c05cdd6719f7dc675e86c2ca8b73a_bWVyY3VyaWFsL2J1bmRsZTIucHk=..780fc16b62e6370f1208895f1e83b6e02c389ee8_bWVyY3VyaWFsL2J1bmRsZTIucHk= 100644
--- a/mercurial/bundle2.py
+++ b/mercurial/bundle2.py
@@ -1822,7 +1822,11 @@
             chunks.extend([node, fnode])
 
     if chunks:
-        bundler.newpart(b'hgtagsfnodes', data=b''.join(chunks))
+        bundler.newpart(
+            b'hgtagsfnodes',
+            mandatory=False,
+            data=b''.join(chunks),
+        )
 
 
 def addpartrevbranchcache(repo, bundler, outgoing):
diff --git a/tests/test-tags.t b/tests/test-tags.t
index 4ee50d98d35c05cdd6719f7dc675e86c2ca8b73a_dGVzdHMvdGVzdC10YWdzLnQ=..780fc16b62e6370f1208895f1e83b6e02c389ee8_dGVzdHMvdGVzdC10YWdzLnQ= 100644
--- a/tests/test-tags.t
+++ b/tests/test-tags.t
@@ -855,7 +855,7 @@
       c4dab0c2fd337eb9191f80c3024830a4889a8f34
       f63cc8fe54e4d326f8d692805d70e092f851ddb1
       40f0358cb314c824a5929ee527308d90e023bc10
-  hgtagsfnodes -- {} (mandatory: True)
+  hgtagsfnodes -- {} (mandatory: False)
   cache:rev-branch-cache -- {} (mandatory: False)
 
 Check that local clone includes cache data