osx: force resync menus when changing keybindings

Normally menu items are updated only when adding or removing
them on osx. They are however not redrawn when just changing
keybindings so the old keybinding is displayed after the change.

Force the menu update to show the updated keybindings.

src/prefs.c

@@ -56,6 +56,7 @@
 #include "ui_utils.h"
 #include "utils.h"
 #include "vte.h"
+#include "osx.h"
 
 #include "gtkcompat.h"
 
@@ -1197,6 +1198,10 @@ on_prefs_dialog_response(GtkDialog *dialog, gint response, gpointer user_data)
 			kb_update(&global_kb_data);
 			tools_create_insert_custom_command_menu_items();
 			keybindings_write_to_file();
+#ifdef MAC_INTEGRATION
+			/* Force re-syncing the menubar to update displayed keybindings. */
+			gtkosx_application_sync_menubar(gtkosx_application_get());
+#endif
 		}
 
 		/* Printing */