diff --git a/docker/routlin-dash/app/factory.py b/docker/routlin-dash/app/factory.py
index 0420628..d50b9cb 100644
--- a/docker/routlin-dash/app/factory.py
+++ b/docker/routlin-dash/app/factory.py
@@ -216,9 +216,14 @@ def table_token_key(spec):
 
 def iter_table_items(items):
     for item in items:
+        if not isinstance(item, dict):
+            continue
         if item.get('type') == 'table':
             yield item
-        for sub in (item.get('items') or [], (item.get('toolbar') or {}).get('items') or []):
+        sub_items = item.get('items')
+        if not isinstance(sub_items, list):
+            sub_items = []
+        for sub in (sub_items, (item.get('toolbar') or {}).get('items') or []):
             yield from iter_table_items(sub)
 
 # Access control ======================================================