diff --git a/umap/static/umap/map.css b/umap/static/umap/map.css
index 8ab5e394..4da92b16 100644
--- a/umap/static/umap/map.css
+++ b/umap/static/umap/map.css
@@ -1352,6 +1352,7 @@ a.add-datalayer:hover,
     display: flex;
     flex-direction: column;
     overflow-y: auto;
+    overflow-x: hidden;
 }
 .umap-popup-content iframe {
     min-width: 310px;