1 files changed, 4 insertions, 0 deletions
diff --git a/ui/gtk.c b/ui/gtk.c
index bdd831c268..3f67a345d1 100644
--- a/ui/gtk.c
+++ b/ui/gtk.c
@@ -1007,6 +1007,10 @@ static gboolean gd_button_event(GtkWidget *widget, GdkEventButton *button,
         btn = INPUT_BUTTON_MIDDLE;
     } else if (button->button == 3) {
         btn = INPUT_BUTTON_RIGHT;
+    } else if (button->button == 8) {
+        btn = INPUT_BUTTON_SIDE;
+    } else if (button->button == 9) {
+        btn = INPUT_BUTTON_EXTRA;
     } else {
         return TRUE;
     }