diff --git a/lib/javascript-static.js b/lib/javascript-static.js
index a72f797c9a4..8793bb2dd8f 100644
--- a/lib/javascript-static.js
+++ b/lib/javascript-static.js
@@ -216,7 +216,7 @@ M.util.show_confirm_dialog = function(e, args) {
 
     YUI(M.yui.loader).use('yui2-container', 'yui2-event', function(Y) {
         var simpledialog = new YAHOO.widget.SimpleDialog('confirmdialog',
-            { width: '300px',
+            {width: '300px',
               fixedcenter: true,
               modal: true,
               visible: false,
@@ -273,8 +273,8 @@ M.util.show_confirm_dialog = function(e, args) {
             }
         };
 
-        var buttons = [ { text: M.str.moodle.cancel, handler: handle_cancel, isDefault: true },
-                        { text: M.str.moodle.yes, handler: handle_yes } ];
+        var buttons = [ {text: M.str.moodle.cancel, handler: handle_cancel, isDefault: true},
+                        {text: M.str.moodle.yes, handler: handle_yes} ];
 
         simpledialog.cfg.queueProperty('buttons', buttons);
 
@@ -538,18 +538,18 @@ function lockoptionsall(formid) {
                 var hide = false;
                 switch (condition) {
                   case 'notchecked':
-                      lock = !form[dependon].checked; break;
+                      lock = !form[dependon].checked;break;
                   case 'checked':
-                      lock = form[dependon].checked; break;
+                      lock = form[dependon].checked;break;
                   case 'noitemselected':
-                      lock = form[dependon].selectedIndex == -1; break;
+                      lock = form[dependon].selectedIndex == -1;break;
                   case 'eq':
-                      lock = get_form_element_value(form, dependon) == value; break;
+                      lock = get_form_element_value(form, dependon) == value;break;
                   case 'hide':
                       // hide as well as disable
-                      hide = true; break;
+                      hide = true;break;
                   default:
-                      lock = get_form_element_value(form, dependon) != value; break;
+                      lock = get_form_element_value(form, dependon) != value;break;
                 }
                 for (var ei in dependons[dependon][condition][value]) {
                     var eltolock = dependons[dependon][condition][value][ei];
@@ -1408,7 +1408,10 @@ M.util.help_icon = {
     instance : null,
     add : function(Y, properties) {
         this.Y = Y;
-        Y.one('#'+properties.id).on('click', this.display, this, properties);
+        var node = Y.one('#'+properties.id);
+        if (node) {
+            node.on('click', this.display, this, properties);
+        }
     },
     display : function(event, args) {
         event.preventDefault();