diff --git a/app/ui.js b/app/ui.js
index e4dfd5af8..316042911 100644
--- a/app/ui.js
+++ b/app/ui.js
@@ -818,13 +818,17 @@ const UI = {
     disableSetting(name) {
         const ctrl = document.getElementById('noVNC_setting_' + name);
         ctrl.disabled = true;
-        ctrl.label.classList.add('noVNC_disabled');
+        if (ctrl.label !== undefined) {
+            ctrl.label.classList.add('noVNC_disabled');
+        }
     },
 
     enableSetting(name) {
         const ctrl = document.getElementById('noVNC_setting_' + name);
         ctrl.disabled = false;
-        ctrl.label.classList.remove('noVNC_disabled');
+        if (ctrl.label !== undefined) {
+            ctrl.label.classList.remove('noVNC_disabled');
+        }
     },
 
 /* ------^-------