Hi Venkatakrishna,
The <br> tag is added in the empty content area by Firefox. This tag is stripped by the ConvertToXhtml filter and if you set the ContentFilters property to None, the <br> tag will remain.
Nevertheless, you can find an example demonstrating how to convert the float inline style to align attribute in the following forum thread:
http://www.telerik.com/community/forums/aspnet-ajax/editor/editor-transforming-align-right-into-float-right.aspx.
Greetings,
Rumen
the Telerik team
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