diff --git a/share/manifest b/share/manifest
index 92f8e91..5781e45 100644
--- a/share/manifest
+++ b/share/manifest
@@ -50,13 +50,13 @@ $css
 # entry point of pdf2htmlEX.Viewer
 # You can override default configuration by passing an object to the constructor of Viewer
 # Refer to DEFAULT_CONFIG in viewer.js for possible keys
-# E.g.
-# new pdf2htmlEX.Viewer({ 'preload_pages' : 1 });
 @pdf2htmlEX.min.js
 """
 <script>
 try{
-  pdf2htmlEX.defaultViewer = new pdf2htmlEX.Viewer();
+  pdf2htmlEX.defaultViewer = new pdf2htmlEX.Viewer({
+    'register_key_handler' : false 
+  });
 }catch(e){}
 </script>
 """
diff --git a/share/pdf2htmlEX.js.in b/share/pdf2htmlEX.js.in
index b993eee..7309878 100644
--- a/share/pdf2htmlEX.js.in
+++ b/share/pdf2htmlEX.js.in
@@ -186,11 +186,6 @@
       // for a lot of times(= #pages), just hope JIT works
       var rect_c = this.$container[0].getBoundingClientRect();
       return [rect_c.left-rect.left, rect_c.top-rect.top];
-      /*
-      var off = this.$p.offset();
-      var off_c = this.$container.offset();
-      return [off_c.left-off.left, off_c.top-off.top];
-      */
     }
   });