+Perhaps we should get rid of the `show_lang`, `show_perpage` and
+`show_sort` configuration items, and simply display the relevant menus
+only when their containers are provided -- e.g. an `mkwsLang` element
+for the language menu. But for now we retain these, as an easier route
+to lightly customise the display than my changing providing a full HTML
+structure.
+