When a Splitter contains both RadPanes with size in percent and free-sized panes, the width of the fomer is calculated properly only after the initial loading and remains the same the the page is resized.

Steps to reproduce:
1.     <telerik:RadSplitter ID="RadSplitter1" runat="server" Width="100%">
            <telerik:RadPane ID="RadPane1" runat="server" Width="10%"></telerik:RadPane>
            <telerik:RadSplitBar ID="RadSplitbar1" runat="server" ></telerik:RadSplitBar>
            <telerik:RadPane ID="RadPane2" runat="server"></telerik:RadPane>
         </telerik:RadSplitter>

2. Resize the browser.

Result: the size of RadPane1 is not recalculated

Temporary workaround:
Set size in perncent to all RadPanes in the Splitter.

The height of a  free-sized RadPane is not calculated properly on layout mode change in Android devices. The issue is reproducible in Firefox for Android.

Add ability to add border decoration to a RadPane/RadSplitter, without breaking the size of the control.

Add ability to add margin/padding to a Radpane, without breaking the size of the control.