diff --git a/hgext/narrow/narrowbundle2.py b/hgext/narrow/narrowbundle2.py
--- a/hgext/narrow/narrowbundle2.py
+++ b/hgext/narrow/narrowbundle2.py
@@ -20,7 +20,6 @@
     changegroup,
     error,
     exchange,
-    extensions,
     narrowspec,
     repair,
     repository,
@@ -31,10 +30,9 @@
     stringutil,
 )
 
-NARROWCAP = 'narrow'
 _NARROWACL_SECTION = 'narrowhgacl'
-_CHANGESPECPART = NARROWCAP + ':changespec'
-_SPECPART = NARROWCAP + ':spec'
+_CHANGESPECPART = 'narrow:changespec'
+_SPECPART = 'narrow:spec'
 _SPECPART_INCLUDE = 'include'
 _SPECPART_EXCLUDE = 'exclude'
 _KILLNODESIGNAL = 'KILL'
@@ -44,12 +42,6 @@
 _CSHEADERSIZE = struct.calcsize(_ELIDEDCSHEADER)
 _MFHEADERSIZE = struct.calcsize(_ELIDEDMFHEADER)
 
-# When advertising capabilities, always include narrow clone support.
-def getrepocaps_narrow(orig, repo, **kwargs):
-    caps = orig(repo, **kwargs)
-    caps[NARROWCAP] = ['v0']
-    return caps
-
 # Serve a changegroup for a client with a narrow clone.
 def getbundlechangegrouppart_narrow(bundler, repo, source,
                                     bundlecaps=None, b2caps=None, heads=None,
@@ -252,8 +244,6 @@
 
 def setup():
     """Enable narrow repo support in bundle2-related extension points."""
-    extensions.wrapfunction(bundle2, 'getrepocaps', getrepocaps_narrow)
-
     getbundleargs = wireprototypes.GETBUNDLE_ARGUMENTS
 
     getbundleargs['narrow'] = 'boolean'
diff --git a/tests/test-narrow-clone-non-narrow-server.t b/tests/test-narrow-clone-non-narrow-server.t
--- a/tests/test-narrow-clone-non-narrow-server.t
+++ b/tests/test-narrow-clone-non-narrow-server.t
@@ -32,7 +32,6 @@
   > EOF
   $ echo hello | hg -R . serve --stdio | \
   >   "$PYTHON" unquote.py | tr ' ' '\n' | grep narrow
-  narrow=v0
   exp-narrow-1
 
   $ cd ..