diff --git a/holoviews/core/options.py b/holoviews/core/options.py
index 597511c34c..b0e6a4a0a8 100644
--- a/holoviews/core/options.py
+++ b/holoviews/core/options.py
@@ -1787,7 +1787,9 @@ def id_offset(cls):
         """
         max_ids = []
         for backend in Store.renderers.keys():
-            store_ids = Store.custom_options(backend=backend).keys()
+            # Ensure store_ids is immediately cast to list to avoid a
+            # race condition (#5533)
+            store_ids = list(Store.custom_options(backend=backend).keys())
             max_id = max(store_ids)+1 if len(store_ids) > 0 else 0
             max_ids.append(max_id)
         # If no backends defined (e.g. plotting not imported) return zero