+val increase_font_size: unit -> unit
+val decrease_font_size: unit -> unit
+val reset_font_size: unit -> unit
+
+val refresh_all_browsers: unit -> unit (** act on all cicBrowsers *)
+val update_font_sizes: unit -> unit
+
+(** {2 singleton instances} *)
+
+val sequentViewer_instance: unit -> sequentViewer
+val sequentsViewer_instance: unit -> sequentsViewer
+
+val mathViewer: unit -> MatitaTypes.mathViewer