--- a/mercurial/manifest.py	Tue Oct 10 10:01:57 2023 +0200
+++ b/mercurial/manifest.py	Tue Oct 10 10:02:05 2023 +0200
@@ -1614,7 +1614,7 @@
         )
 
         self.index = self._revlog.index
-        self._generaldelta = self._revlog._generaldelta
+        self._generaldelta = self._revlog.delta_config.general_delta
 
     def get_revlog(self):
         """return an actual revlog instance if any