--- a/mercurial/debugcommands.py	Wed Jun 01 01:13:13 2022 +0200
+++ b/mercurial/debugcommands.py	Wed Jun 01 00:59:44 2022 +0200
@@ -1877,11 +1877,13 @@
 
     fm = ui.formatter(b'debugindex', opts)
 
+    revlog = getattr(store, b'_revlog', store)
+
     return revlog_debug.debug_index(
         ui,
         repo,
         formatter=fm,
-        revlog=store,
+        revlog=revlog,
         full_node=ui.debugflag,
     )