The ContextMenu popup is not position properly relative to its target element when the page is horizontally scrolled in Edge. The problem is reproducible with R2 2018. Steps tp reproduce: 1. Run the code below and scroll the page to the right 2. Right click over a number <!DOCTYPE html> <html xmlns="http://www.w3.org/1999/xhtml"> <head runat="server"> <title></title> </head> <body> <form id="form1" runat="server"> <telerik:RadScriptManager ID="RadScriptManager1" runat="server"> </telerik:RadScriptManager> <telerik:RadContextMenu ID="rcmMenu" runat="server"> <Targets> <telerik:ContextMenuTagNameTarget TagName="a" /> </Targets> <Items> <telerik:RadMenuItem Text="Menu Item 1" Value="a" /> <telerik:RadMenuItem Text="Menu Item 2" Value="b" /> </Items> </telerik:RadContextMenu> <div style="width: 3500px; height: 100px; position: relative; background-color: yellow;"> <a style="position: absolute; left: 1000px; top: 40px;" onclick="return showMenu(event);">1000</a> <a style="position: absolute; left: 2000px; top: 40px;" onclick="return showMenu(event);">2000</a> <a style="position: absolute; left: 3000px; top: 40px;" onclick="return showMenu(event);">3000</a> </div> </form> </body> </html>