when TabView is inside Stack and item is added dynamically to the RadTabView, the content of this first item does not layout as expected. 

<StackLayout>
    <Button Text="Add" Clicked="OnAddClicked" />
    <Button Text="Remove" Clicked="OnRemoveClicked" Margin="0,5,0,5" />
    <Button Text="Clear" Clicked="OnClearClicked" />
        
        
    <telerikPrimitives:RadTabView BackgroundColor="Red" x:Name="tabView" AutomationId="tabView"/>
</StackLayout>