function Worksheet_BeforeRightClick(Target, Cancel) {
    let icbc = Application.CommandBars.Item("cell").Controls
    for(let i = 1; i <= icbc.Count; i++) {
        if(icbc.Item(i).Tag == "brccm") {
            icbc.Item(i).Delete()
        }
    }
    if(Application.Intersect(Target, Range("b1:b10")) != null) {
        icbc.Add(msoControlButton, undefined, undefined, 6, true)
        icbc.Caption = "New Context Menu Item"
        icbc.OnAction = "MyMacro"
        icbc.Tag = "brccm"
    }
}