Thank you for reporting this issue. It seems there is an issue with the Load "Windowless" mode
button Click() event. We will investigate it further and try to fix it as soon as possible.
In the meantime you can use this link to test the FirstLook demo in Firefox: http://demos.telerik.com/silverlight/Default.aspx?windowless=true#HtmlPlaceholder/FirstLook
and this link: http://demos.telerik.com/silverlight/Default.aspx?windowless=true#HtmlPlaceholder/WindowIntegration
to test the Window Integration demo.
I also updated your Telerik points accordingly.
the Telerik team
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