diff --git a/crates/oa-desktop/src/behavior.rs b/crates/oa-desktop/src/behavior.rs
--- a/crates/oa-desktop/src/behavior.rs
+++ b/crates/oa-desktop/src/behavior.rs
@@ -1120,1 +1120,5 @@
+#[cfg(test)]
+#[path = "../../../harness/experiments/behavior-layout-scene-20260912/mod.rs"]
+mod behavior_layout_scene_experiment;
+
 struct BoxItem {
@@ -1446,2 +1450,4 @@
+            #[cfg(test)]
+            behavior_layout_scene_experiment::resolve_row_anchor(*id, y);
             if ordered {
                 let slot = scenario::Slot {