diff --git a/src/pyj/book_list/custom_list.pyj b/src/pyj/book_list/custom_list.pyj
index 0b55e6373a..080236dba7 100644
--- a/src/pyj/book_list/custom_list.pyj
+++ b/src/pyj/book_list/custom_list.pyj
@@ -62,7 +62,7 @@ def render_field(field, mi, book_id):  # {{{
         return book_id + ''
     field_metadata = library_data.field_metadata
     fm = field_metadata[field]
-    if not fm:
+    if not fm or not mi:
         return
     val = mi[field]
     if val is undefined or val is None: