It seems this is quite unusual behavior with our RadPanelBar control. I am afraid that I am not able to reproduce such issue locally using a simply RadPanelBar with RadControls version Q2 2013 SP1 (2013,.2. 717. 45)
for .NET 4.5 .
Could you please try to reproduce the issue with the attached sample project and explain exactly how we can replicate it. That way we will be able to inspect it thoroughly.
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