diff -u b/core/modules/node/node.module b/core/modules/node/node.module
--- b/core/modules/node/node.module
+++ b/core/modules/node/node.module
@@ -2010,7 +2010,9 @@
       $allowed_types = array_filter($visibility['node_type']['types']);
     }
     if (empty($allowed_types)) {
-      // There are no node type visibility settings so we have nothing to do.
+      // There are no node types selected in visibility settings so there is
+      // nothing to do.
+      // @see node_form_block_form_alter()
       return;
     }
     $node = menu_get_object();