Index: src/wp-includes/css/editor.css
===================================================================
--- src/wp-includes/css/editor.css	(revision 27747)
+++ src/wp-includes/css/editor.css	(working copy)
@@ -73,6 +73,10 @@
 	width: calc( 100% - 36px );
 }
 
+.mce-wp-help .mce-window-head {
+	border-bottom: none;
+}
+
 .mce-textbox {
 	border: 1px solid #ddd;
 	-webkit-border-radius: 0;
Index: src/wp-includes/js/tinymce/plugins/wordpress/plugin.js
===================================================================
--- src/wp-includes/js/tinymce/plugins/wordpress/plugin.js	(revision 27747)
+++ src/wp-includes/js/tinymce/plugins/wordpress/plugin.js	(working copy)
@@ -182,7 +182,8 @@
 			url: tinymce.baseURL + '/wp-mce-help.php',
 			width: 450,
 			height: 420,
-			inline: 1
+			inline: 1,
+			classes: 'wp-help'
 		});
 	});
 
Index: src/wp-includes/js/tinymce/wp-mce-help.php
===================================================================
--- src/wp-includes/js/tinymce/wp-mce-help.php	(revision 27747)
+++ src/wp-includes/js/tinymce/wp-mce-help.php	(working copy)
@@ -27,51 +27,35 @@
 		min-width: 0;
 	}
 
-	#tabs-wrap {
+	.wp-core-ui #tabs {
+		margin-top: 5px;
+		padding: 0 6px;
 		position: absolute;
 		top: 0;
+		right: 0;
+		left: 0;
+		height: 31px;
+		z-index: 1;
 	}
 
-	#tabs {
-		box-shadow: 0 3px 5px rgba( 255, 255, 255, 0.2 );
-		margin: 0;
-		padding: 0;
+	.wp-core-ui #tabs a {
 		position: relative;
-		-webkit-user-select: none;
-		-moz-user-select: none;
-		-ms-user-select: none;
-		user-select: none;
-	}
-
-	#tabs a {
-		-webkit-transition: none;
-		transition: none;
-	}
-	
-	#tabs-wrap #tabs > a {
 		float: left;
-		font-size: 14px;
+		padding: 6px 10px;
+		margin: 0;
 		height: 18px;
 		line-height: 18px;
-		margin: 0;
-		padding: 7px 10px;
-		position: relative;
 		text-decoration: none;
-		border-right: 1px solid #ddd;
-		background-color: #eee;
-		color: inherit;
-	}
-
-	#tabs > a:active,
-	#tabs > a:focus {
-		outline: none;
+		-webkit-transition: none;
+		transition: none;
 	}
 
-	#tabs-wrap #tabs .active,
-	#tabs-wrap #tabs .active:hover {
-		color: #333;
+	#tabs a.active {
+		margin: -1px -1px 0;
 		background: #fff;
-		border-bottom: 1px solid #fff;
+		border: 1px solid #ddd;
+		border-bottom: none;
+		color: #333;
 	}
 
 	#tabs .active:after {
@@ -83,8 +67,8 @@
 		border-top: 1px solid #ddd;
 		height: 360px;
 		margin: 0;
-		margin-top: 32px;
-		overflow-y: scroll;
+		margin-top: 34px;
+		overflow: auto;
 		padding: 10px 16px;
 	}
 
@@ -151,13 +135,11 @@
 	document.body.className = document.body.className.replace(/windows/, 'macos');
 </script>
 
-<div id="tabs-wrap">
-	<div id="tabs">
-		<a id="tab1" href="javascript:flipTab(1)" title="<?php esc_attr_e('Basics of Rich Editing'); ?>" accesskey="1" class="active"><?php _e('Basics'); ?></a>
-		<a id="tab2" href="javascript:flipTab(2)" title="<?php esc_attr_e('Advanced use of the Rich Editor'); ?>" accesskey="2"><?php _e('Advanced'); ?></a>
-		<a id="tab3" href="javascript:flipTab(3)" title="<?php esc_attr_e('Hotkeys'); ?>" accesskey="3"><?php _e('Hotkeys'); ?></a>
-		<a id="tab4" href="javascript:flipTab(4)" title="<?php esc_attr_e('About the software'); ?>" accesskey="4"><?php _e('About'); ?></a>
-	</div>
+<div id="tabs">
+	<a id="tab1" href="javascript:flipTab(1)" title="<?php esc_attr_e('Basics of Rich Editing'); ?>" accesskey="1" class="active"><?php _e('Basics'); ?></a>
+	<a id="tab2" href="javascript:flipTab(2)" title="<?php esc_attr_e('Advanced use of the Rich Editor'); ?>" accesskey="2"><?php _e('Advanced'); ?></a>
+	<a id="tab3" href="javascript:flipTab(3)" title="<?php esc_attr_e('Hotkeys'); ?>" accesskey="3"><?php _e('Hotkeys'); ?></a>
+	<a id="tab4" href="javascript:flipTab(4)" title="<?php esc_attr_e('About the software'); ?>" accesskey="4"><?php _e('About'); ?></a>
 </div>
 
 <div id="flipper" class="wrap">