diff --git a/hammond-gtk/src/appnotif.rs b/hammond-gtk/src/appnotif.rs
index 806936c..22b0c6e 100644
--- a/hammond-gtk/src/appnotif.rs
+++ b/hammond-gtk/src/appnotif.rs
@@ -5,7 +5,7 @@ use gtk::prelude::*;
 use std::cell::RefCell;
 use std::rc::Rc;
 
-#[derive(Debug, Clone)]
+#[derive(Debug, Clone, Copy)]
 pub enum UndoState {
     Shown,
     Hidden,