Gtk.ImageMenuItem

const Gtk = imports.gi.Gtk;

let image_menu_item = new Gtk.ImageMenuItem({
    accel_group: value,
    always_show_image: value,
    image: value,
    use_stock: value,
});
  

A GtkImageMenuItem is a menu item which has an icon next to the text label.

Note that the user can disable display of menu icons, so make sure to still fill in the text label.