+1  A: 

My first thought is that you need to show us some code, but realising you probably need to narrow things down my second thought is that you need to deal with ASP.NET's browser downscaling.

If you aren't aware of it, ASP.NET has a frustrating feature of considering IE better (really no other way to put it) than Firefox and other browsers. See here and here for some details. Check the rendered source in both browsers (and others!).

Not saying this is the issue, just that it could be.

annakata
Thanks for answer, let me check these two links. I can't use IE because Firefox is client's preference.
Muhammad Kashif Nadeem
There's no reason why you can't use IE for debugging (I would never suggest IE out of choice!)
annakata
+1  A: 

This problem is in Telerik RadEditor & in 2009 Q1 release. To fix the problem in the current SP2 build, please set the new TableLayoutCssFile property of RadEditor to point to some external css file (it could be empty), e.g.

<telerik:RadEditor runat="server" ID="RadEditor1" TableLayoutCssFile="~/Empty.css"></telerik:RadEditor>

http://www.telerik.com/community/forums/aspnet-ajax/editor/radeditor-forces-page-load-twice.aspx

Muhammad Kashif Nadeem