diff --git a/hgext/narrow/narrowwirepeer.py b/hgext/narrow/narrowwirepeer.py
--- a/hgext/narrow/narrowwirepeer.py
+++ b/hgext/narrow/narrowwirepeer.py
@@ -21,17 +21,8 @@
 )
 
 def uisetup():
-    extensions.wrapfunction(wireprotov1server, '_capabilities', addnarrowcap)
     wireprotov1peer.wirepeer.narrow_widen = peernarrowwiden
 
-def addnarrowcap(orig, repo, proto):
-    """add the narrow capability to the server"""
-    caps = orig(repo, proto)
-    caps.append(wireprototypes.NARROWCAP)
-    if repo.ui.configbool('experimental', 'narrowservebrokenellipses'):
-        caps.append(wireprototypes.ELLIPSESCAP)
-    return caps
-
 def reposetup(repo):
     def wirereposetup(ui, peer):
         def wrapped(orig, cmd, *args, **kwargs):
diff --git a/mercurial/wireprotov1server.py b/mercurial/wireprotov1server.py
--- a/mercurial/wireprotov1server.py
+++ b/mercurial/wireprotov1server.py
@@ -286,6 +286,11 @@
         caps.append('bundle2=' + urlreq.quote(capsblob))
     caps.append('unbundle=%s' % ','.join(bundle2.bundlepriority))
 
+    if repo.ui.configbool('experimental', 'narrow'):
+        caps.append(wireprototypes.NARROWCAP)
+        if repo.ui.configbool('experimental', 'narrowservebrokenellipses'):
+            caps.append(wireprototypes.ELLIPSESCAP)
+
     return proto.addcapabilities(repo, caps)
 
 # If you are writing an extension and consider wrapping this function. Wrap