diff --git a/src/caoscrawler/crawl.py b/src/caoscrawler/crawl.py
index d21e6e2521578dc407e445d8220506677be84e26..53172dd2d99c3ab6b317083b899871e978be4672 100644
--- a/src/caoscrawler/crawl.py
+++ b/src/caoscrawler/crawl.py
@@ -646,8 +646,8 @@ class Crawler(object):
         registered_identifiable = self.identifiableAdapter.get_registered_identifiable(record)
         if registered_identifiable is None:
             return False
-        refs = self.identifiableAdapter.get_identifying_referencing_entities(referencing_entities,
-                                                                             registered_identifiable)
+        refs = self.identifiableAdapter.get_identifying_referencing_entities(
+            referencing_entities, registered_identifiable)
         if any(el is None for el in refs):
             return True
 
@@ -671,6 +671,11 @@ class Crawler(object):
 
         So the returned mapping maps ids of entities to the ids of objects which are referring
         to them.
+
+        .. todo::
+
+          This method takes about 2/3 of the time of synchronize(), it might be a good
+          optimization candidate.
         """
         # TODO we need to treat children of RecordTypes somehow.
         references: dict[int, dict[str, list[Union[int, None]]]] = {}
diff --git a/src/doc/conf.py b/src/doc/conf.py
index cf32b2e7c090119f7ba419b8c498d262e1157a6c..3248726ed63dd80fdee7c06da3c27caace93f22c 100644
--- a/src/doc/conf.py
+++ b/src/doc/conf.py
@@ -219,3 +219,5 @@ autodoc_default_options = {
     'member-order': 'bysource',
     'special-member': ["__init__"],
 }
+
+todo_include_todos = True