diff -r dcaa2df1f688 -r a93e52f0b6ff mercurial/revlogutils/randomaccessfile.py
--- a/mercurial/revlogutils/randomaccessfile.py	Mon Dec 11 22:27:59 2023 +0100
+++ b/mercurial/revlogutils/randomaccessfile.py	Thu Dec 07 02:07:16 2023 +0100
@@ -116,8 +116,6 @@
         if initial_cache:
             self._cached_chunk_position, self._cached_chunk = initial_cache
 
-        self._delay_buffer = None
-
     def clear_cache(self):
         self._cached_chunk = b''
         self._cached_chunk_position = 0
@@ -133,12 +131,7 @@
 
     def _open(self, mode=b'r'):
         """Return a file object"""
-        if self._delay_buffer is None:
-            return self.opener(self.filename, mode=mode)
-        else:
-            return appender(
-                self.opener, self.filename, mode, self._delay_buffer
-            )
+        return self.opener(self.filename, mode=mode)
 
     @contextlib.contextmanager
     def _read_handle(self):