diff --git a/gtk.c b/gtk.c
index b2655b1..9643d19 100644
--- a/gtk.c
+++ b/gtk.c
@@ -415,6 +415,8 @@ void activate_timer(frontend *fe)
 
 static void window_destroy(GtkWidget *widget, gpointer data)
 {
+    frontend *fe = (frontend *)data;
+    deactivate_timer(fe);
     gtk_main_quit();
 }