In general the RadMenu uses the ResolveClientUrl
methods to resolve URLs defined via the NavigateUrl property and MSDN documentation states the following: "The URL returned by this method is relative to the folder containing the source file in which the control is instantiated."
. This means that if the RadMenu is on a page requested via https, then the page to which it navigates will be requested via https as well. This could be verified on our online demos here
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