The RadWindow is merely a container control and it should not modify the content you place inside, therefore such a feature is not available in it. The RadEditor has it to allow you to generate content with the same style as the parent page, e.g. for a CMS-like environment. The main difference is that the iframe the Editor uses is controlled by us and is, for starters, always from the same domain, so it can be accessed. This is not always the case with a RadWindow, it can load an external page, e.g. www.mifrosoft.com or bing.com and it would not be possible to access such pages to modify their styles. Also, with its accent on reuasbility, loading another page in the same RadWindow that copies stylesheets would most likely result in a broken page.
the Telerik team
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