diff --git a/src/Fancybox/plugins/Html/Html.js b/src/Fancybox/plugins/Html/Html.js
index fda4ca1..012df34 100644
--- a/src/Fancybox/plugins/Html/Html.js
+++ b/src/Fancybox/plugins/Html/Html.js
@@ -539,10 +539,12 @@ export class Html {
         this.loadAjaxContent(slide);
         break;
 
-      case "iframe":
       case "pdf":
       case "video":
       case "map":
+        slide.preload = false;
+
+      case "iframe":
         this.loadIframeContent(slide);
 
         break;