How to dismiss contextual menu

Hi all!
In a DesktopCanvas I can make appear a contextual menu just simply pressing the shift key and then move the mouse into the canvas, by adding this code in the Canvas event ‘MouseEnter’:

If Keyboard.AsyncShiftKey Then
  Var popMenu As DesktopMenuItem
  popMenu = EditMenu.Clone
  Var selectedMenu As DesktopMenuItem
  selectedMenu = popMenu.Popup
  if selectedMenu <> nil then
    if selectedMenu.text = "&Undo" then
      TextField1.text=  selectedMenu.text
End If

Now, if I do nothing (=meaning I do not click anywhere and move the mouse outside of the canvas control, I would like the contextual menu to disappear.
I tried in different ways, but I couldn’t managed that. Any suggestion ?

I could consider to combine a Timer + checking for the mouse position and ‘simulating’ the pression of the ‘esc’ key, but I wonder if I can take advantage of the event ‘MouseExit’ or other simpler options.