So far we haven't been able to reproduce the problem on your site - I see that you are communicating with Alex on this subject.
Could you please tell me, have you tried opening your site from a different machine? In theory such problem could occur if for some reason not all resources have been loaded - for example if they are filtered by a firewall, however without being able to reproduce the same behavior it is not possible to say if this is the real reason.
the Telerik team
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