Please excuse us for the caused inconvenience! We are aware of this issue and it is will be inspected by our developers although I cannot provide a firm estimate when a fix will be available. You can use the PITS Issue
related to the encountered problem to track its status.
As you noticed, the encountered behavior is related the scrollable content of the RadDockZone. Please avoid using a RadDockZone with fixed height for the time being, if this is possible in your scenario.
the Telerik team
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