Comment 4 for bug 698501

I can reproduce this with the following patch.

diff --git a/gschem/src/x_preview.c b/gschem/src/x_preview.c
index be76d64..60f88fc 100644
--- a/gschem/src/x_preview.c
+++ b/gschem/src/x_preview.c
@@ -131,6 +131,7 @@ preview_callback_expose (GtkWidget *widget,
   preview_w_current->pl = pango_cairo_create_layout (preview_w_current->cr);

   gdk_region_get_rectangles (event->region, &rectangles, &n_rectangles);
+ g_debug ("Preview redraw");
   o_redraw_rects (preview_w_current, rectangles, n_rectangles);
   g_free (rectangles);