If a RadWindow contains a RadComboBox, and the RadWindow allows the "Move" behavior, there exists a rendering problem with all major browsers: If the dropdown area of the RadComboBox is expanded during a move operation of the RadWindow, the dropdown area stays behind while the RadComboBox and the RadWindow are moved. Steps to reproduce: 1.) Create a new Telerik C# Web Application 2.) Use the code of the attached Default.aspx file 3.) Run the project and follow the instructions of the Default.aspx page
You should hide the drop down on window move: <telerik:RadWindow Visible="true" Title="Test window" VisibleOnPageLoad="true" runat="server" ID="radwindow" Behaviors="Move,Close" Width="300" Height="50" OnClientDragStart="hideDropDown"> <ContentTemplate> <telerik:RadComboBox runat="server" ID="combo" Width="100%"> <Items> <telerik:RadComboBoxItem Text="foo" /> <telerik:RadComboBoxItem Text="bar" /> <telerik:RadComboBoxItem Text="baz" /> </Items> </telerik:RadComboBox> </ContentTemplate> </telerik:RadWindow> <script type="text/javascript"> function hideDropDown(sender, args) { var combo = $find("<%= combo.ClientID %>"); combo.hideDropDown(); } </script>