diff --git a/crates/oa-desktop/src/behavior/scenario.rs b/crates/oa-desktop/src/behavior/scenario.rs
index 6d60ce1f..8ba4abeb 100644
--- a/crates/oa-desktop/src/behavior/scenario.rs
+++ b/crates/oa-desktop/src/behavior/scenario.rs
@@ -3234,12 +3234,24 @@ mod tests {
                 .iter()
                 .any(|l| l.id == steps[1] && l.dashed && l.label.contains("reply"))
         );
-        assert!(
-            scene
-                .boxes
-                .iter()
-                .any(|b| b.id == steps[0] && b.rect.width == 8.)
+        assert_eq!(
+            scene.activations,
+            vec![super::super::scenario_activation::Segment {
+                call: steps[0],
+                receiver,
+                scope: owner,
+                rect: Rectangle::new(
+                    Point::new(scene.lanes[&receiver] - 6., 148.),
+                    Size::new(12., 92.),
+                ),
+                column: 0,
+                finish: super::super::scenario_activation::Finish::Reply(steps[1]),
+            }]
         );
+        let call_line = scene.lines.iter().find(|line| line.id == steps[0]).unwrap();
+        let reply_line = scene.lines.iter().find(|line| line.id == steps[1]).unwrap();
+        assert_eq!(call_line.points.last().unwrap().y, 148.);
+        assert_eq!(reply_line.points.first().unwrap().y, 240.);
         let mut reply = State::default();
         reply
             .update(result, Event::Start(owner, Tool::Message))
diff --git a/crates/oa-desktop/src/behavior/scenario_lifecycle/union_tests.rs b/crates/oa-desktop/src/behavior/scenario_lifecycle/union_tests.rs
index 86fa0cce..1ca1f1fa 100644
--- a/crates/oa-desktop/src/behavior/scenario_lifecycle/union_tests.rs
+++ b/crates/oa-desktop/src/behavior/scenario_lifecycle/union_tests.rs
@@ -443,8 +443,8 @@ fn test_only_upstream_row_offsets_update_lifetime_segments_and_endpoints_without
         let birth = f.message(f.owner, MessageKind::Create);
         let c1 = f.message(f.owner, MessageKind::Call);
         let c2 = f.message(f.owner, MessageKind::Call);
-        f.reply(f.owner, c2);
-        f.reply(f.owner, c1);
+        let r2 = f.reply(f.owner, c2);
+        let r1 = f.reply(f.owner, c1);
         let death = f.message(f.owner, MessageKind::Delete);
         let document = f.document();
         let before = document.snapshot();
@@ -454,6 +454,15 @@ fn test_only_upstream_row_offsets_update_lifetime_segments_and_endpoints_without
         });
         assert_eq!(moved.rows[&birth].1, baseline.rows[&birth].1 + 60.);
         assert_eq!(moved.rows[&death].1, baseline.rows[&death].1 + 60.);
+        for scene in [&baseline, &moved] {
+            assert_eq!(scene.activations.len(), 2);
+            for (call, reply) in [(c1, r1), (c2, r2)] {
+                assert!(scene.activations.iter().any(|segment| {
+                    segment.call == call
+                        && segment.finish == Finish::Reply(reply)
+                }));
+            }
+        }
         for (a, b) in baseline.activations.iter().zip(&moved.activations) {
             assert_eq!(
                 (a.call, a.receiver, a.scope, a.column, a.finish),