diff --git a/experiments/2024-12-09/src/ui.rs b/experiments/2024-12-09/src/ui.rs
index 9622de845..ee34ce324 100644
--- a/experiments/2024-12-09/src/ui.rs
+++ b/experiments/2024-12-09/src/ui.rs
@@ -2,6 +2,7 @@ use std::fmt;
 
 use crate::geometry::{HandleAny, Operation, Triangle, Vertex};
 
+#[derive(Clone)]
 pub struct OperationView {
     operation: HandleAny,
     selected: Option<usize>,