Forum post: http://forums.asp.net/thread/1611639.aspx
We should clone all the positioning and size properties of the element to construct the parent div.
<asp:Panel ID="PanelSideBar" runat="server" Style="position: absolute; top: 100px;
left: 10px; bottom: 25px; width: 200px" BackColor="Beige">
</asp:Panel>
<cc1:RoundedCornersExtender ID="RCExtender" runat="server" TargetControlID="PanelSideBar">
</cc1:RoundedCornersExtender>
Comments: Workaround found, see comments.
We should clone all the positioning and size properties of the element to construct the parent div.
<asp:Panel ID="PanelSideBar" runat="server" Style="position: absolute; top: 100px;
left: 10px; bottom: 25px; width: 200px" BackColor="Beige">
</asp:Panel>
<cc1:RoundedCornersExtender ID="RCExtender" runat="server" TargetControlID="PanelSideBar">
</cc1:RoundedCornersExtender>
Comments: Workaround found, see comments.