diff --git a/src/pretix/static/pretixpresale/js/widget/widget.js b/src/pretix/static/pretixpresale/js/widget/widget.js
index 2dff90b8b..f8bafa6aa 100644
--- a/src/pretix/static/pretixpresale/js/widget/widget.js
+++ b/src/pretix/static/pretixpresale/js/widget/widget.js
@@ -648,7 +648,7 @@ var shared_root_computed = {
         return form_target;
     },
     useIframe: function () {
-        return window.innerWidth >= 800 && (this.skip_ssl || site_is_secure());
+        return Math.min(screen.width, window.innerWidth) >= 800 && (this.skip_ssl || site_is_secure());
     }
 };