diff --git a/blocks/dock.js b/blocks/dock.js
index 25e1243dd06..f742b31376a 100644
--- a/blocks/dock.js
+++ b/blocks/dock.js
@@ -131,7 +131,7 @@ M.blocks.dock = {
         }
 
         var dockcontrol = Y.Node.create('<div class="'+M.blocks.dock.cfg.css.controls+'"></div>');
-        var removeall = Y.Node.create('<img src="'+get_image_url('t/dock_to_block', 'moodle')+'" alt="'+mstr.block.undockall+'" title="'+mstr.block.undockall+'" />');
+        var removeall = Y.Node.create('<img src="'+M.util.image_url('t/dock_to_block', 'moodle')+'" alt="'+mstr.block.undockall+'" title="'+mstr.block.undockall+'" />');
         removeall.on('removeall|click', this.remove_all, this);
         dockcontrol.appendChild(removeall);
         this.node.appendChild(dockcontrol);
@@ -309,7 +309,7 @@ M.blocks.dock = {
             }
 
             var moveto = Y.Node.create('<a class="moveto customcommand requiresjs"></a>');
-            moveto.append(Y.Node.create('<img src="'+get_image_url('t/dock_to_block', 'moodle')+'" alt="'+mstr.block.undockitem+'" title="'+mstr.block.undockitem+'" />'));
+            moveto.append(Y.Node.create('<img src="'+M.util.image_url('t/dock_to_block', 'moodle')+'" alt="'+mstr.block.undockitem+'" title="'+mstr.block.undockitem+'" />'));
             if (location.href.match(/\?/)) {
                 moveto.set('href', location.href+'&dock='+this.id);
             } else {
@@ -353,7 +353,7 @@ M.blocks.dock = {
                 Y.Event.purgeElement(Y.Node.getDOMNode(moveto), false, 'click');
                 if (moveto.hasClass('customcommand')) {
                     moveto.all('img').each(function(movetoimg){
-                        movetoimg.setAttribute('src', get_image_url('t/dock_to_block', 'moodle'));
+                        movetoimg.setAttribute('src', M.util.image_url('t/dock_to_block', 'moodle'));
                         movetoimg.setAttribute('alt', mstr.block.undockitem);
                         movetoimg.setAttribute('title', mstr.block.undockitem);
                     }, this);
@@ -448,7 +448,7 @@ M.blocks.dock = {
                 moveto.on('movetodock|click', this.move_to_dock, this);
                 if (moveto.hasClass('customcommand')) {
                     moveto.all('img').each(function(movetoimg){
-                        movetoimg.setAttribute('src', get_image_url('t/block_to_dock', 'moodle'));
+                        movetoimg.setAttribute('src', M.util.image_url('t/block_to_dock', 'moodle'));
                         movetoimg.setAttribute('alt', mstr.block.addtodock);
                         movetoimg.setAttribute('title', mstr.block.addtodock);
                     }, this);
diff --git a/comment/comment.js b/comment/comment.js
index 30f93ade908..ed018f26ce3 100644
--- a/comment/comment.js
+++ b/comment/comment.js
@@ -158,7 +158,7 @@ M.core_comment = {
                     var val = template.get('innerHTML');
                     val = val.replace('___name___', list[i].username);
                     if (list[i]['delete']||newcmt) {
-                        list[i].content = '<div class="comment-delete"><a href="###" id ="comment-delete-'+this.client_id+'-'+list[i].id+'" title="'+mstr.moodle.deletecomment+'"><img src="'+M.cfg.wwwroot+'/pix/t/delete.gif" /></a></div>' + list[i].content;
+                        list[i].content = '<div class="comment-delete"><a href="###" id ="comment-delete-'+this.client_id+'-'+list[i].id+'" title="'+mstr.moodle.deletecomment+'"><img src="'+M.util.image_url('t/delete', 'core')+'" /></a></div>' + list[i].content;
                     }
                     val = val.replace('___time___', list[i].time);
                     val = val.replace('___picture___', list[i].avatar);
@@ -279,11 +279,11 @@ M.core_comment = {
                     // show
                     this.load(page);
                     container.setStyle('display', 'block');
-                    img.src=M.cfg.wwwroot+'/pix/t/expanded.png';
+                    img.src=M.util.image_url('t/expanded', 'core');
                 } else {
                     // hide
                     container.setStyle('display', 'none');
-                    img.src=M.cfg.wwwroot+'/pix/t/collapsed.png';
+                    img.src=M.util.image_url('t/collapsed', 'core');
                     ta.set('value','');
                 }
                 //toggle_textarea.apply(ta, [false]);
@@ -318,7 +318,7 @@ M.core_comment = {
             },
             wait: function() {
                 var container = Y.one('#comment-list-'+this.client_id);
-                container.set('innerHTML', '<div style="text-align:center"><img src="'+M.cfg.wwwroot+'/pix/i/loading.gif'+'" /></div>');
+                container.set('innerHTML', '<div style="text-align:center"><img src="'+M.util.image_url('i/loading', 'core')+'" /></div>');
             }
         });
 
diff --git a/lib/ajax/ajaxlib.php b/lib/ajax/ajaxlib.php
index 21f9311b300..9b5f04f38d8 100644
--- a/lib/ajax/ajaxlib.php
+++ b/lib/ajax/ajaxlib.php
@@ -215,8 +215,6 @@ class page_requirements_manager {
         // Otherwise, in some situations, users will get warnings about insecure content
         // on sercure pages from their web browser.
 
-        //TODO: problem here is we may need this in some included JS - move this somehow to the very beginning
-        //      right after the YUI loading
         $this->M_cfg = array(
             'wwwroot'             => $CFG->httpswwwroot, // Yes, really. See above.
             'sesskey'             => sesskey(),
diff --git a/lib/javascript-static.js b/lib/javascript-static.js
index 0019d880c81..523a79b2bea 100644
--- a/lib/javascript-static.js
+++ b/lib/javascript-static.js
@@ -14,6 +14,29 @@ M.yui.add_module = function(modules) {
 	}
 };
 
+/**
+ * Various utility functions
+ */
+M.util = {
+	/**
+	 * Returns url for images.
+	 */
+	image_url: function(imagename, component) {
+	    var url = M.cfg.wwwroot + '/theme/image.php?theme=' + M.cfg.theme + '&image=' + imagename;
+	
+	    if (M.cfg.themerev > 0) {
+	        url = url + '&rev=' + M.cfg.themerev;
+	    }
+	
+	    if (component != '' && component != 'moodle' && component != 'core') {
+	        url = url + '&component=' + component;
+	    }
+	
+	    return url;
+	}
+}
+
+
 function launch_filemanager(options) {
     Y.use('core_filemanager', function() {
             var client_id = options.client_id;
@@ -1398,21 +1421,6 @@ function frame_breakout(e, properties) {
     this.setAttribute('target', properties.framename);
 }
 
-function get_image_url(imagename, component) {
-    var url = M.cfg.wwwroot + '/theme/image.php?theme=' + M.cfg.theme + '&image=' + imagename;
-
-    if (M.cfg.themerev > 0) {
-        url = url + '&rev=' + M.cfg.themerev;
-    }
-
-    if (component != '' && component != 'moodle' && component != 'core') {
-        url = url + '&component=' + component;
-    }
-
-    return url;
-}
-
-
 
 // ===== Deprecated core Javascript functions for Moodle ====
 //       DO NOT USE!!!!!!!