It's important to point out that widgets should only be marked as
realized very late in the process. Even GTK widgets don't get this
right.
https://bugzilla.gnome.org/show_bug.cgi?id=726717
* @widget: a #GtkWidget
* @realized: %TRUE to mark the widget as realized
*
- * Marks the widget as being realized.
+ * Marks the widget as being realized. This function must only be
+ * called after all #GdkWindows for the @widget have been created
+ * and registered.
*
* This function should only ever be called in a derived widget's
* “realize” or “unrealize” implementation.