viewtopic.php?f=6&t=7951&p=21007&hilit=maximize#p21007
<script type="text/javascript">
function FCKeditor_OnComplete( editorInstance )
{
var oEditor = FCKeditorAPI.GetInstance( editorInstance.Name ) ;
oEditor.Commands.GetCommand('FitWindow').Execute();
}
</Script>Ticket can be close

Re: Maximize the editor size
<html> <head> <title></title> <script type="text/javascript" src="fckeditor.js"></script> <script Language="Javascript" type="text/javascript"> window.onload = function() { var oFCKeditor = new FCKeditor('description'); oFCKeditor.BasePath = ''; oFCKeditor.Config["CustomConfigurationsPath"] = "custom_fckconfig.js" ; oFCKeditor.Value = 'Editor default text'; oFCKeditor.ReplaceTextarea() ; } function FCKeditor_OnComplete( editorInstance ) { alert( editorInstance.Name ) ; editorInstance.Commands.GetCommand('FitWindow').Execute(); } </script> </head> <body> <textarea name="description" cols="100" rows="50" class="FormText"></textarea> </body> </html>