diff --git a/swh/storage/converters.py b/swh/storage/converters.py
--- a/swh/storage/converters.py
+++ b/swh/storage/converters.py
@@ -222,9 +222,13 @@
                 parents.append(parent)
 
     metadata = db_revision["metadata"]
-    extra_headers = db_revision.get("extra_headers", ())
-    if not extra_headers and metadata and "extra_headers" in metadata:
-        extra_headers = db_to_git_headers(metadata.pop("extra_headers"))
+    extra_headers = db_revision["extra_headers"]
+    if not extra_headers:
+        if metadata and "extra_headers" in metadata:
+            extra_headers = db_to_git_headers(metadata.pop("extra_headers"))
+        else:
+            # For older versions of the database that were not migrated to schema v161
+            extra_headers = ()
 
     return Revision(
         id=db_revision["id"],