diff --git a/portal/assets/css/ynh_overlay.css b/portal/assets/css/ynh_overlay.css
index ab4fc50..1604004 100644
--- a/portal/assets/css/ynh_overlay.css
+++ b/portal/assets/css/ynh_overlay.css
@@ -20,9 +20,12 @@
 html.ynh-panel-active {
   /* Disable any scrolling on app */
   overflow: hidden;
+
 }
 
-body {/*overflow-y: scroll;*/}
+body {
+  overflow-y: auto;
+}
 
 #ynh-overlay-switch,
 #ynh-overlay-switch *,
@@ -70,14 +73,14 @@ body {/*overflow-y: scroll;*/}
 
 /* Background */
 #ynh-overlay {
-  visibility: hidden;
+  overflow-y: hidden;
   position: fixed;
   top:0;
   left: 0;
   width: 100%;
   height: 100%;
   z-index: 9999999;
-  display: block;
+  display: none;
   border: none;
   color:#fff;
   background: #41444F;
@@ -176,4 +179,4 @@ body {/*overflow-y: scroll;*/}
     width: 80px;
     height: 75px;
   }
-}
+}
\ No newline at end of file
diff --git a/portal/assets/js/ynh_portal.js b/portal/assets/js/ynh_portal.js
index 84453c6..3a79a21 100644
--- a/portal/assets/js/ynh_portal.js
+++ b/portal/assets/js/ynh_portal.js
@@ -265,7 +265,8 @@ function init_portal_button_and_overlay()
   var portalOverlay = document.createElement('iframe');
   portalOverlay.src = "/yunohost/sso/portal.html";
   portalOverlay.setAttribute("id","ynh-overlay");
-  portalOverlay.setAttribute("style","visibility: hidden;"); // make sure the overlay is invisible already when loading it
+  portalOverlay.setAttribute("style","display: none;"); // make sure the overlay is invisible already when loading it
+  // portalOverlay.setAttribute("class","ynh-fadeOut"); // set overlay as masked when loading it
   document.body.insertBefore(portalOverlay, null);
 
   // Inject portal button
@@ -286,10 +287,12 @@ function init_portal_button_and_overlay()
       Element.toggleClass(portalOverlay, 'ynh-active');
 
       if (Element.hasClass(portalOverlay, 'ynh-active')) {
+          portalOverlay.setAttribute("style","display: block;");
           meta_viewport.setAttribute('content', meta_viewport_content);
           Element.addClass(portalOverlay, 'ynh-fadeIn');
           Element.removeClass(portalOverlay, 'ynh-fadeOut');
       } else {
+          portalOverlay.setAttribute("style","display: none;");
           meta_viewport.setAttribute('content', "width=device-width");
           Element.removeClass(portalOverlay, 'ynh-fadeIn');
           Element.addClass(portalOverlay, 'ynh-fadeOut');
@@ -341,6 +344,7 @@ function init_portal()
   });
 }
 
+
 function tweak_portal_when_in_iframe()
 {
     // Set class to body to show we're in overlay
@@ -369,4 +373,4 @@ function tweak_portal_when_in_iframe()
             window.parent.location.href = logoutButton.getAttribute("href");
         });
     }
-}
+}
\ No newline at end of file