Added a copy of Firebug Lite for debugging purposes. License is uncertain but being treated as MPL. (If is is not MPL then it is under something more permissive that permits relicensing anyway)
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title>{#advhr.advhr_desc}</title>
<script type="text/javascript" src="../../tiny_mce_popup.js"></script>
<script type="text/javascript" src="js/rule.js"></script>
<script type="text/javascript" src="../../utils/mctabs.js"></script>
<script type="text/javascript" src="../../utils/form_utils.js"></script>
<link href="css/advhr.css" rel="stylesheet" type="text/css" />
<base target="_self" />
</head>
<body>
<form onsubmit="AdvHRDialog.update();return false;" action="#">
<div class="tabs">
<ul>
<li id="general_tab" class="current"><span><a href="javascript:mcTabs.displayTab('general_tab','general_panel');" onmousedown="return false;">{#advhr.advhr_desc}</a></span></li>
</ul>
</div>
<div class="panel_wrapper">
<div id="general_panel" class="panel current">
<table border="0" cellpadding="4" cellspacing="0">
<tr>
<td><label for="width">{#advhr_dlg.width}</label></td>
<td nowrap="nowrap">
<input id="width" name="width" type="text" value="" />
<select name="width2" id="width2">
<option value="">px</option>
<option value="%">%</option>
</select>
</td>
</tr>
<tr>
<td><label for="size">{#advhr_dlg.size}</label></td>
<td><select id="size" name="size">
<option value="">Normal</option>
<option value="1">1</option>
<option value="2">2</option>
<option value="3">3</option>
<option value="4">4</option>
<option value="5">5</option>
</select></td>
</tr>
<tr>
<td><label for="noshade">{#advhr_dlg.noshade}</label></td>
<td><input type="checkbox" name="noshade" id="noshade" class="radio" /></td>
</tr>
</table>
</div>
</div>
<div class="mceActionPanel">
<div style="float: left">
<input type="button" id="insert" name="insert" value="{#insert}" onclick="AdvHRDialog.update();" />
</div>
<div style="float: right">
<input type="button" id="cancel" name="cancel" value="{#cancel}" onclick="tinyMCEPopup.close();" />
</div>
</div>
</form>
</body>
</html>