The default behavior of RadSkinManager if you put it in a Master Page is to skin all the controls in the content pages and user controls which do not have an explicitly set Skin
property or are not listed in the RadSkinManager's TargetControls
collection. In other words, if you do not include any controls in the TargetControls collection and do not set skins explicitly, all RadControls will be skinned by RadSkinManager with the currently chosen skin. If you observe another behavior, there must be some issue on the page.
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