[balsa/wip/gtk4] main-window: Fix enable_modify_messages

[Peter Bloomfield <peterb src gnome org>]

commit dca047eef59767bf0aadc79427b3acbdaedadeda
Author: Peter Bloomfield <PeterBloomfield bellsouth net>
Date:   Thu Aug 2 18:46:19 2018 -0400

    main-window: Fix enable_modify_messages

 src/main-window.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/src/main-window.c b/src/main-window.c
index 57a0aeaad..ce3a0d2e7 100644
--- a/src/main-window.c
+++ b/src/main-window.c
@@ -2567,7 +2567,7 @@ bw_enable_message_menus(BalsaWindow * window, guint msgno)
         g_list_free_full(messages, g_object_unref);
 
         mailbox = balsa_index_get_mailbox(bindex);
-        enable_modify_message_actions =
+        enable_modify_message_actions = enable_message_actions &&
             (mailbox != NULL && !libbalsa_mailbox_get_readonly(mailbox));
 
         enable_store = (balsa_app.address_book_list != NULL);