diff --git a/web/viewer.html b/web/viewer.html
index 08b75468f..be758dbb9 100644
--- a/web/viewer.html
+++ b/web/viewer.html
@@ -3,6 +3,32 @@
     <head>
         <title>Simple pdf.js page viewer</title>
         <link rel="stylesheet" href="viewer.css"/>
+
+        <script type="text/javascript" src="compatibility.js"></script>
+
+        <!-- PDFJSSCRIPT_INCLUDE_BUILD -->
+        <script type="text/javascript" src="../src/core.js"></script> <!-- PDFJSSCRIPT_REMOVE -->
+        <script type="text/javascript" src="../src/util.js"></script>  <!-- PDFJSSCRIPT_REMOVE -->
+        <script type="text/javascript" src="../src/canvas.js"></script>  <!-- PDFJSSCRIPT_REMOVE -->
+        <script type="text/javascript" src="../src/obj.js"></script>  <!-- PDFJSSCRIPT_REMOVE -->
+        <script type="text/javascript" src="../src/function.js"></script> <!-- PDFJSSCRIPT_REMOVE -->
+        <script type="text/javascript" src="../src/charsets.js"></script>  <!-- PDFJSSCRIPT_REMOVE -->
+        <script type="text/javascript" src="../src/cidmaps.js"></script>  <!-- PDFJSSCRIPT_REMOVE -->
+        <script type="text/javascript" src="../src/colorspace.js"></script>  <!-- PDFJSSCRIPT_REMOVE -->
+        <script type="text/javascript" src="../src/crypto.js"></script>  <!-- PDFJSSCRIPT_REMOVE -->
+        <script type="text/javascript" src="../src/evaluator.js"></script>  <!-- PDFJSSCRIPT_REMOVE -->
+        <script type="text/javascript" src="../src/fonts.js"></script>  <!-- PDFJSSCRIPT_REMOVE -->
+        <script type="text/javascript" src="../src/glyphlist.js"></script>  <!-- PDFJSSCRIPT_REMOVE -->
+        <script type="text/javascript" src="../src/image.js"></script>  <!-- PDFJSSCRIPT_REMOVE -->
+        <script type="text/javascript" src="../src/metrics.js"></script>  <!-- PDFJSSCRIPT_REMOVE -->
+        <script type="text/javascript" src="../src/parser.js"></script>  <!-- PDFJSSCRIPT_REMOVE -->
+        <script type="text/javascript" src="../src/pattern.js"></script>  <!-- PDFJSSCRIPT_REMOVE -->
+        <script type="text/javascript" src="../src/stream.js"></script>  <!-- PDFJSSCRIPT_REMOVE -->
+        <script type="text/javascript" src="../src/worker.js"></script>  <!-- PDFJSSCRIPT_REMOVE -->
+        <script type="text/javascript" src="../external/jpgjs/jpg.js"></script>  <!-- PDFJSSCRIPT_REMOVE -->
+        <script type="text/javascript">PDFJS.workerSrc = '../src/worker_loader.js';</script> <!-- PDFJSSCRIPT_REMOVE -->
+        <script type="text/javascript" src="viewer.js"></script>
+
     </head>
 
   <body>
@@ -93,31 +119,5 @@
 
     <div id="loading">Loading... 0%</div>
     <div id="viewer"></div>
-
-    <script type="text/javascript" src="compatibility.js"></script>
-
-    <!-- PDFJSSCRIPT_INCLUDE_BUILD -->
-    <script type="text/javascript" src="../src/core.js"></script> <!-- PDFJSSCRIPT_REMOVE -->
-    <script type="text/javascript" src="../src/util.js"></script>  <!-- PDFJSSCRIPT_REMOVE -->
-    <script type="text/javascript" src="../src/canvas.js"></script>  <!-- PDFJSSCRIPT_REMOVE -->
-    <script type="text/javascript" src="../src/obj.js"></script>  <!-- PDFJSSCRIPT_REMOVE -->
-    <script type="text/javascript" src="../src/function.js"></script> <!-- PDFJSSCRIPT_REMOVE -->
-    <script type="text/javascript" src="../src/charsets.js"></script>  <!-- PDFJSSCRIPT_REMOVE -->
-    <script type="text/javascript" src="../src/cidmaps.js"></script>  <!-- PDFJSSCRIPT_REMOVE -->
-    <script type="text/javascript" src="../src/colorspace.js"></script>  <!-- PDFJSSCRIPT_REMOVE -->
-    <script type="text/javascript" src="../src/crypto.js"></script>  <!-- PDFJSSCRIPT_REMOVE -->
-    <script type="text/javascript" src="../src/evaluator.js"></script>  <!-- PDFJSSCRIPT_REMOVE -->
-    <script type="text/javascript" src="../src/fonts.js"></script>  <!-- PDFJSSCRIPT_REMOVE -->
-    <script type="text/javascript" src="../src/glyphlist.js"></script>  <!-- PDFJSSCRIPT_REMOVE -->
-    <script type="text/javascript" src="../src/image.js"></script>  <!-- PDFJSSCRIPT_REMOVE -->
-    <script type="text/javascript" src="../src/metrics.js"></script>  <!-- PDFJSSCRIPT_REMOVE -->
-    <script type="text/javascript" src="../src/parser.js"></script>  <!-- PDFJSSCRIPT_REMOVE -->
-    <script type="text/javascript" src="../src/pattern.js"></script>  <!-- PDFJSSCRIPT_REMOVE -->
-    <script type="text/javascript" src="../src/stream.js"></script>  <!-- PDFJSSCRIPT_REMOVE -->
-    <script type="text/javascript" src="../src/worker.js"></script>  <!-- PDFJSSCRIPT_REMOVE -->
-    <script type="text/javascript" src="../external/jpgjs/jpg.js"></script>  <!-- PDFJSSCRIPT_REMOVE -->
-    <script type="text/javascript">PDFJS.workerSrc = '../src/worker_loader.js';</script> <!-- PDFJSSCRIPT_REMOVE -->
-    <script type="text/javascript" src="viewer.js"></script>
-
   </body>
 </html>
diff --git a/web/viewer.js b/web/viewer.js
index f4088ec40..7408182d8 100644
--- a/web/viewer.js
+++ b/web/viewer.js
@@ -678,6 +678,9 @@ window.addEventListener('load', function webViewerLoad(evt) {
     document.getElementById('fileInput').setAttribute('hidden', 'true');
   else
     document.getElementById('fileInput').value = null;
+
+  var sidebarScrollView = document.getElementById('sidebarScrollView');
+  sidebarScrollView.addEventListener('scroll', updateThumbViewArea, true);
 }, true);
 
 window.addEventListener('unload', function webViewerUnload(evt) {
@@ -717,7 +720,6 @@ window.addEventListener('scroll', function webViewerScroll(evt) {
 }, true);
 
 
-var sidebarScrollView = document.getElementById('sidebarScrollView');
 var thumbnailTimer;
 
 function updateThumbViewArea() {
@@ -737,7 +739,6 @@ function updateThumbViewArea() {
   }, delay);
 }
 
-sidebarScrollView.addEventListener('scroll', updateThumbViewArea, true);
 window.addEventListener('transitionend', updateThumbViewArea, true);
 window.addEventListener('webkitTransitionEnd', updateThumbViewArea, true);
 
