diff --git a/unix/gtkwin.c b/unix/gtkwin.c
index 2ed7fffe..74b0a2d8 100644
--- a/unix/gtkwin.c
+++ b/unix/gtkwin.c
@@ -4597,6 +4597,8 @@ void new_session_window(Conf *conf, const char *geometry_string)
 {
     struct gui_data *inst;
 
+    prepare_session(conf);
+
     /*
      * Create an instance structure and initialise to zeroes
      */