This is a known issue with our RadPanelBar control and this is caused in this specific case - ExpandMode
is set to "FullExpandedItem
" and one of sibling items contains less number of child items and that item is expanded first. After that when you try to expand any other sibling item that has more number of child items - the scroll bar is shown.
I am afraid that there is no workaround for this case at this moment. I will post here more information as soon as there is an update regarding that problem.
the Telerik team
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