diff --git a/portal/assets/css/ynhpanel.css b/portal/assets/css/ynhpanel.css
index d895790..45aa8ee 100644
--- a/portal/assets/css/ynhpanel.css
+++ b/portal/assets/css/ynhpanel.css
@@ -56,14 +56,14 @@ body {/*overflow-y: scroll;*/}
 
 /* Background */
 #ynh-overlay {
-  display: block;
+  visibility: hidden;
   position: fixed;
   top:0;
   left: 0;
   width: 100%;
   height: 100%;
   z-index: 9999999;
-  opacity: 0;
+  display: block;
   border: none;
   color:#fff;
   background: #41444F;
@@ -79,12 +79,24 @@ body {/*overflow-y: scroll;*/}
 
 /*FadeIn*/
 @-webkit-keyframes fadeIn {
-  0% {opacity: 0;}
-  100% {opacity: 1;}
+  0% {
+    visibility: hidden;
+    opacity:0;
+  }
+  100% {
+    visibility: visible;
+    opacity: 1;
+  }
 }
 @keyframes fadeIn {
-  0% {opacity: 0;}
-  100% {opacity: 1;}
+  0% {
+    visibility: hidden;
+    opacity: 0;
+  }
+  100% {
+    visibility: visible;
+    opacity: 1;
+  }
 }
 
 .ynh-fadeIn {
@@ -106,12 +118,24 @@ body {/*overflow-y: scroll;*/}
 
 /*FadeOut*/
 @-webkit-keyframes fadeOut {
-  0% {opacity: 1;}
-  100% {opacity: 0;}
+  0% {
+    visibility: visible;
+    opacity: 1;
+  }
+  100% {
+    visibility: hidden;
+    opacity: 0;
+  }
 }
 @keyframes fadeOut {
-  0% {opacity: 1;}
-  100% {opacity: 0;}
+  0% {
+    visibility: visible;
+    opacity: 1;
+  }
+  100% {
+    visibility: hidden;
+    opacity: 0;
+  }
 }
 .ynh-fadeOut {
   -webkit-animation-name: fadeOut;
diff --git a/portal/assets/js/ynhpanel.js b/portal/assets/js/ynhpanel.js
index 6fc4c66..b104c4a 100644
--- a/portal/assets/js/ynhpanel.js
+++ b/portal/assets/js/ynhpanel.js
@@ -192,8 +192,7 @@ var dragg = function(id) {
       // Reset dragging status
       dragged = false;
   });
-}
-
+};
 
 /* Smallest DOMReady
   http://dustindiaz.com/smallest-domready-ever
@@ -239,7 +238,7 @@ domReady(function(){
   var overlay = document.createElement('iframe');
   overlay.src = "/yunohost/sso/info.html";
   overlay.setAttribute("id","ynh-overlay");
-  overlay.setAttribute("style","opacity:0"); // make sure the overlay is invisible already when loading it
+  overlay.setAttribute("style","visibility: hidden;"); // make sure the overlay is invisible already when loading it
 
   document.body.insertBefore(overlay, null);
 
@@ -294,5 +293,4 @@ domReady(function(){
   };
   r.send();
 
-
 });