diff --git a/umap/static/umap/js/modules/schema.js b/umap/static/umap/js/modules/schema.js
index 97f3d777..e733739b 100644
--- a/umap/static/umap/js/modules/schema.js
+++ b/umap/static/umap/js/modules/schema.js
@@ -375,6 +375,7 @@ export const SCHEMA = {
   },
   captionControl: {
     type: Boolean,
+    nullable: true,
     label: translate('Display the caption control'),
     default: true,
   },