diff --git a/web/viewer.js b/web/viewer.js
index bda09ed05..ec05c7135 100644
--- a/web/viewer.js
+++ b/web/viewer.js
@@ -573,22 +573,29 @@ var PDFView = {
         break;
     }
   },
-  
-  pinSidebar: function pdfViewPinSidebar() {
-  
-    var sidebar = document.getElementById("sidebar");
-    var pinIcon = document.getElementById("pinIcon");
 
-    sidebar.className = sidebar.className.replace( /(?:^|\s)released(?!\S)/ , '' );
-    sidebar.className = sidebar.className.replace( /(?:^|\s)pinned(?!\S)/ , '' );
-    pinIcon.className = pinIcon.className.replace( /(?:^|\s)released(?!\S)/ , '' );
-    pinIcon.className = pinIcon.className.replace( /(?:^|\s)pinned(?!\S)/ , '' );
-    
-    var newClass = this.pinState ? " pinned" : " released";
-    
+  pinSidebar: function pdfViewPinSidebar() {
+    var sidebar = document.getElementById('sidebar');
+    var pinIcon = document.getElementById('pinIcon');
+
+    sidebar.className = sidebar.className.replace(
+                          /(?:^|\s)released(?!\S)/ ,
+                          '');
+    sidebar.className = sidebar.className.replace(
+                          /(?:^|\s)pinned(?!\S)/ ,
+                          '');
+    pinIcon.className = pinIcon.className.replace(
+                          /(?:^|\s)released(?!\S)/ ,
+                          '');
+    pinIcon.className = pinIcon.className.replace(
+                          /(?:^|\s)pinned(?!\S)/ ,
+                          '');
+
+    var newClass = this.pinState ? ' pinned' : ' released';
+
     sidebar.className += newClass;
     pinIcon.className += newClass;
-    
+
     this.pinState = !this.pinState;
   },