diff --git a/src/black/lines.py b/src/black/lines.py
index f1de1f59235..01208c5fa7d 100644
--- a/src/black/lines.py
+++ b/src/black/lines.py
@@ -716,7 +716,7 @@ def _maybe_empty_lines_for_class_or_def(  # noqa: C901
             # statement in the same level, we always want a blank line if there's
             # something with a body preceding.
             elif (
-                Preview.blank_line_between_nested_and_def_stub_file
+                Preview.blank_line_between_nested_and_def_stub_file in current_line.mode
                 and self.previous_line.depth > current_line.depth
             ):
                 newlines = 1