[gnome-nibbles/arnaudb/modernize-code] Fix a bug.

[Arnaud B. <arnaudb src gnome org>]

commit 06cf4ba107b386c2ba35f5522e0f846929448c80
Author: Arnaud Bonatti <arnaud bonatti gmail com>
Date:   Tue Jun 2 15:40:07 2020 +0200

    Fix a bug.
    
    Ctrl-N during first-run was
    allowing a crash on cancel.

 src/nibbles-window.vala | 4 ++++
 1 file changed, 4 insertions(+)
---
diff --git a/src/nibbles-window.vala b/src/nibbles-window.vala
index f3ec096..878f5e6 100644
--- a/src/nibbles-window.vala
+++ b/src/nibbles-window.vala
@@ -163,6 +163,10 @@ private class NibblesWindow : ApplicationWindow
             FirstRun first_run_panel = new FirstRun ();
             first_run_panel.show ();
             main_stack.add_named (first_run_panel, "first-run");
+
+            new_game_action.set_enabled (false);
+            pause_action.set_enabled (false);
+
             main_stack.set_visible_child (first_run_panel);
         }
         else