diff -r bc884e31b8c8 -r 9796cf108e4e mercurial/localrepo.py
--- a/mercurial/localrepo.py	Fri Jan 08 18:07:33 2021 +0530
+++ b/mercurial/localrepo.py	Fri Jan 08 21:34:16 2021 +0530
@@ -607,7 +607,9 @@
                     storevfs,
                     requirements,
                 )
-            else:
+            elif ui.configbool(
+                b'experimental', b'sharesafe-warn-outdated-shares'
+            ):
                 ui.warn(
                     _(
                         b'warning: source repository supports share-safe functionality.'