diff --git a/umap/static/umap/js/modules/ui/dialog.js b/umap/static/umap/js/modules/ui/dialog.js
index ae72c2a5..f85b7d54 100644
--- a/umap/static/umap/js/modules/ui/dialog.js
+++ b/umap/static/umap/js/modules/ui/dialog.js
@@ -4,7 +4,8 @@ import { translate } from '../i18n.js'
 export default class Dialog {
   constructor(parent) {
     this.parent = parent
-    this.container = DomUtil.create('dialog', 'umap-dialog window', this.parent)
+    this.className = 'umap-dialog window'
+    this.container = DomUtil.create('dialog', this.className, this.parent)
     DomEvent.disableClickPropagation(this.container)
     DomEvent.on(this.container, 'contextmenu', DomEvent.stopPropagation) // Do not activate our custom context menu.
     DomEvent.on(this.container, 'wheel', DomEvent.stopPropagation)
@@ -35,7 +36,7 @@ export default class Dialog {
     else this.container.show()
     if (className) {
       // Reset
-      this.container.className = 'umap-dialog'
+      this.container.className = this.className
       this.container.classList.add(...className.split(' '))
     }
     const buttonsContainer = DomUtil.create('ul', 'buttons', this.container)