--- a/mercurial/upgrade_utils/actions.py	Tue Jan 11 09:56:03 2022 +0100
+++ b/mercurial/upgrade_utils/actions.py	Tue Jan 11 21:40:08 2022 +0100
@@ -243,7 +243,7 @@
     name = b'share-safe'
     _requirement = requirements.SHARESAFE_REQUIREMENT
 
-    default = False
+    default = True
 
     description = _(
         b'old shared repositories do not share source repository '