diff --git a/umap/static/umap/js/modules/data/features.js b/umap/static/umap/js/modules/data/features.js
index 7f5f6ffa..ee168ece 100644
--- a/umap/static/umap/js/modules/data/features.js
+++ b/umap/static/umap/js/modules/data/features.js
@@ -329,7 +329,7 @@ class Feature {
     }
     for (const key of keys) {
       const value = this.properties[key]
-      if (value) return value.trim()
+      if (value) return String(value).trim()
     }
     return this.datalayer.getName().trim()
   }