[gthumb] added missing reference to history menu

[Paolo Bacchilega <paobac src gnome org>]

commit 859ba91c9d2b166277f1be9a50de501fb92b87f1
Author: Paolo Bacchilega <paobac src gnome org>
Date:   Sun Oct 20 12:01:58 2019 +0200

    added missing reference to history menu

 gthumb/gth-browser.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/gthumb/gth-browser.c b/gthumb/gth-browser.c
index 58f724bf..74151675 100644
--- a/gthumb/gth-browser.c
+++ b/gthumb/gth-browser.c
@@ -4556,7 +4556,7 @@ gth_browser_init (GthBrowser *browser)
                button = _gtk_menu_button_new_for_header_bar ("document-open-recent-symbolic");
                gtk_widget_set_tooltip_text (button, _("History"));
 
-               browser->priv->history_menu = G_MENU (gtk_builder_get_object (builder, "visited-locations"));
+               browser->priv->history_menu = g_object_ref (G_MENU (gtk_builder_get_object (builder, 
"visited-locations")));
                gtk_menu_button_set_menu_model (GTK_MENU_BUTTON (button), G_MENU_MODEL 
(gtk_builder_get_object (builder, "menu")));
                gtk_widget_show (button);
                gtk_box_pack_start (GTK_BOX (gth_browser_get_headerbar_section (browser, 
GTH_BROWSER_HEADER_SECTION_BROWSER_NAVIGATION)), button, FALSE, FALSE, 0);