diff --git a/lisp/window.el b/lisp/window.el
index a11293d372..3d064e12d7 100644
--- a/lisp/window.el
+++ b/lisp/window.el
@@ -10596,6 +10596,17 @@ window-prefix-map
   "0" #'delete-windows-on)
 (define-key ctl-x-map "w" window-prefix-map)
 
+(defun foo-it (&rest rest)
+  (with-current-buffer (get-buffer-create "*foo*")
+    (goto-char (point-max))
+    (when rest
+      (insert (format "%s" (car rest)))
+      (setq rest (cdr rest))
+      (while rest
+	(insert (format " .. %s" (car rest)))
+	(setq rest (cdr rest)))
+      (insert "\n"))))
+
 (provide 'window)
 
 ;;; window.el ends here
diff --git a/src/gtkutil.c b/src/gtkutil.c
index a6bba096a4..a4bd34c142 100644
--- a/src/gtkutil.c
+++ b/src/gtkutil.c
@@ -2028,6 +2028,10 @@ xg_wm_set_size_hint (struct frame *f, long int flags, bool user_position)
 		 &f->output_data.xp->size_hints,
 		 sizeof (size_hints)) != 0)
     {
+      call7 (Qfoo_it, intern ("xg_wm_set_size_hint"),
+	     intern ("line_height"), make_fixnum (FRAME_LINE_HEIGHT (f)),
+	     intern ("base_height"), make_fixnum (size_hints.base_height),
+	     intern ("height_inc"), make_fixnum (size_hints.height_inc));
       block_input ();
       gtk_window_set_geometry_hints (GTK_WINDOW (FRAME_GTK_OUTER_WIDGET (f)),
                                      NULL, &size_hints, hint_flags);
diff --git a/src/window.c b/src/window.c
index f116b9a9d7..cc02fc0520 100644
--- a/src/window.c
+++ b/src/window.c
@@ -8394,6 +8393,7 @@ syms_of_window (void)
   DEFSYM (Qheader_line_format, "header-line-format");
   DEFSYM (Qtab_line_format, "tab-line-format");
   DEFSYM (Qno_other_window, "no-other-window");
+  DEFSYM (Qfoo_it, "foo-it");
 
   DEFVAR_LISP ("temp-buffer-show-function", Vtemp_buffer_show_function,
 	       doc: /* Non-nil means call as function to display a help buffer.