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>{#advanced_dlg.charmap_title}</title>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1" />
<script type="text/javascript" src="../../tiny_mce_popup.js"></script>
<script type="text/javascript" src="js/charmap.js"></script>
<base target="_self" />
</head>
<body id="charmap" style="display:none">
<table align="center" border="0" cellspacing="0" cellpadding="2">
<tr>
<td colspan="2" class="title">{#advanced_dlg.charmap_title}</td>
</tr>
<tr>
<td id="charmapView" rowspan="2" align="left" valign="top">
<!-- Chars will be rendered here -->
</td>
<td width="100" align="center" valign="top">
<table border="0" cellpadding="0" cellspacing="0" width="100" style="height:100px">
<tr>
<td id="codeV"> </td>
</tr>
<tr>
<td id="codeN"> </td>
</tr>
</table>
</td>
</tr>
<tr>
<td valign="bottom" style="padding-bottom: 3px;">
<table width="100" align="center" border="0" cellpadding="2" cellspacing="0">
<tr>
<td align="center" style="border-left: 1px solid #666699; border-top: 1px solid #666699; border-right: 1px solid #666699;">HTML-Code</td>
</tr>
<tr>
<td style="font-size: 16px; font-weight: bold; border-left: 1px solid #666699; border-bottom: 1px solid #666699; border-right: 1px solid #666699;" id="codeA" align="center"> </td>
</tr>
<tr>
<td style="font-size: 1px;"> </td>
</tr>
<tr>
<td align="center" style="border-left: 1px solid #666699; border-top: 1px solid #666699; border-right: 1px solid #666699;">NUM-Code</td>
</tr>
<tr>
<td style="font-size: 16px; font-weight: bold; border-left: 1px solid #666699; border-bottom: 1px solid #666699; border-right: 1px solid #666699;" id="codeB" align="center"> </td>
</tr>
</table>
</td>
</tr>
</table>
</body>
</html>