Index: wp-includes/js/thickbox/loadingAnimation.gif
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Cannot display: file marked as a binary type.
svn:mime-type = application/octet-stream
Index: wp-includes/js/thickbox/thickbox.css
===================================================================
--- wp-includes/js/thickbox/thickbox.css	(revision 22368)
+++ wp-includes/js/thickbox/thickbox.css	(working copy)
@@ -160,3 +160,16 @@
 	margin-bottom:-1px;
 	_margin-bottom:1px;
 }
+
+.tb-close-icon {
+	background: url('tb-close.png') no-repeat;
+	height: 15px;
+	width: 15px;
+}
+
+@media only screen and (-webkit-min-device-pixel-ratio: 1.5) {
+	.tb-close-icon {
+		background: url('tb-close-2x.png') no-repeat;
+		background-size: 15px;
+	}
+}
\ No newline at end of file
Index: wp-includes/js/thickbox/tb-close-2x.png
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Cannot display: file marked as a binary type.
svn:mime-type = application/octet-stream

Property changes on: wp-includes/js/thickbox/tb-close-2x.png
___________________________________________________________________
Added: svn:mime-type
   + application/octet-stream

Index: wp-includes/js/thickbox/thickbox.js
===================================================================
--- wp-includes/js/thickbox/thickbox.js	(revision 22368)
+++ wp-includes/js/thickbox/thickbox.js	(working copy)
@@ -8,9 +8,6 @@
 if ( typeof tb_pathToImage != 'string' ) {
 	var tb_pathToImage = thickboxL10n.loadingAnimation;
 }
-if ( typeof tb_closeImage != 'string' ) {
-	var tb_closeImage = thickboxL10n.closeImage;
-}
 
 /*!!!!!!!!!!!!!!!!! edit below this line at your own risk !!!!!!!!!!!!!!!!!!!!!!!*/
 
@@ -59,7 +56,7 @@
 		}
 
 		if(caption===null){caption="";}
-		jQuery("body").append("<div id='TB_load'><img src='"+imgLoader.src+"' /></div>");//add loader to the page
+		jQuery("body").append("<div id='TB_load'><img src='"+imgLoader.src+"' width='208' /></div>");//add loader to the page
 		jQuery('#TB_load').show();//show loader
 
 		var baseURL;
@@ -132,7 +129,7 @@
 
 			TB_WIDTH = imageWidth + 30;
 			TB_HEIGHT = imageHeight + 60;
-			jQuery("#TB_window").append("<a href='' id='TB_ImageOff' title='"+thickboxL10n.close+"'><img id='TB_Image' src='"+url+"' width='"+imageWidth+"' height='"+imageHeight+"' alt='"+caption+"'/></a>" + "<div id='TB_caption'>"+caption+"<div id='TB_secondLine'>" + TB_imageCount + TB_PrevHTML + TB_NextHTML + "</div></div><div id='TB_closeWindow'><a href='#' id='TB_closeWindowButton' title='"+thickboxL10n.close+"'><img src='" + tb_closeImage + "' /></a></div>");
+			jQuery("#TB_window").append("<a href='' id='TB_ImageOff' title='"+thickboxL10n.close+"'><img id='TB_Image' src='"+url+"' width='"+imageWidth+"' height='"+imageHeight+"' alt='"+caption+"'/></a>" + "<div id='TB_caption'>"+caption+"<div id='TB_secondLine'>" + TB_imageCount + TB_PrevHTML + TB_NextHTML + "</div></div><div id='TB_closeWindow'><a href='#' id='TB_closeWindowButton' title='"+thickboxL10n.close+"'><div class='tb-close-icon'></div></a></div>");
 
 			jQuery("#TB_closeWindowButton").click(tb_remove);
 
@@ -200,7 +197,7 @@
 					urlNoQuery = url.split('TB_');
 					jQuery("#TB_iframeContent").remove();
 					if(params['modal'] != "true"){//iframe no modal
-						jQuery("#TB_window").append("<div id='TB_title'><div id='TB_ajaxWindowTitle'>"+caption+"</div><div id='TB_closeAjaxWindow'><a href='#' id='TB_closeWindowButton' title='"+thickboxL10n.close+"'><img src='" + tb_closeImage + "' /></a></div></div><iframe frameborder='0' hspace='0' src='"+urlNoQuery[0]+"' id='TB_iframeContent' name='TB_iframeContent"+Math.round(Math.random()*1000)+"' onload='tb_showIframe()' style='width:"+(ajaxContentW + 29)+"px;height:"+(ajaxContentH + 17)+"px;' >"+thickboxL10n.noiframes+"</iframe>");
+						jQuery("#TB_window").append("<div id='TB_title'><div id='TB_ajaxWindowTitle'>"+caption+"</div><div id='TB_closeAjaxWindow'><a href='#' id='TB_closeWindowButton' title='"+thickboxL10n.close+"'><div class='tb-close-icon'></div></a></div></div><iframe frameborder='0' hspace='0' src='"+urlNoQuery[0]+"' id='TB_iframeContent' name='TB_iframeContent"+Math.round(Math.random()*1000)+"' onload='tb_showIframe()' style='width:"+(ajaxContentW + 29)+"px;height:"+(ajaxContentH + 17)+"px;' >"+thickboxL10n.noiframes+"</iframe>");
 					}else{//iframe modal
 					jQuery("#TB_overlay").unbind();
 						jQuery("#TB_window").append("<iframe frameborder='0' hspace='0' src='"+urlNoQuery[0]+"' id='TB_iframeContent' name='TB_iframeContent"+Math.round(Math.random()*1000)+"' onload='tb_showIframe()' style='width:"+(ajaxContentW + 29)+"px;height:"+(ajaxContentH + 17)+"px;'>"+thickboxL10n.noiframes+"</iframe>");
@@ -208,7 +205,7 @@
 			}else{// not an iframe, ajax
 					if(jQuery("#TB_window").css("visibility") != "visible"){
 						if(params['modal'] != "true"){//ajax no modal
-						jQuery("#TB_window").append("<div id='TB_title'><div id='TB_ajaxWindowTitle'>"+caption+"</div><div id='TB_closeAjaxWindow'><a href='#' id='TB_closeWindowButton'><img src='" + tb_closeImage + "' /></a></div></div><div id='TB_ajaxContent' style='width:"+ajaxContentW+"px;height:"+ajaxContentH+"px'></div>");
+						jQuery("#TB_window").append("<div id='TB_title'><div id='TB_ajaxWindowTitle'>"+caption+"</div><div id='TB_closeAjaxWindow'><a href='#' id='TB_closeWindowButton'><div class='tb-close-icon'></div></a></div></div><div id='TB_ajaxContent' style='width:"+ajaxContentW+"px;height:"+ajaxContentH+"px'></div>");
 						}else{//ajax modal
 						jQuery("#TB_overlay").unbind();
 						jQuery("#TB_window").append("<div id='TB_ajaxContent' class='TB_modal' style='width:"+ajaxContentW+"px;height:"+ajaxContentH+"px;'></div>");
Index: wp-admin/includes/ms.php
===================================================================
--- wp-admin/includes/ms.php	(revision 22368)
+++ wp-admin/includes/ms.php	(working copy)
@@ -773,7 +773,6 @@
 <script type="text/javascript">
 //<![CDATA[
 var tb_pathToImage = "../../wp-includes/js/thickbox/loadingAnimation.gif";
-var tb_closeImage = "../../wp-includes/js/thickbox/tb-close.png";
 //]]>
 </script>
 <?php