diff --git a/crates/oa-desktop/src/behavior/state_label_canvas_tests.rs b/crates/oa-desktop/src/behavior/state_label_canvas_tests.rs
index ee46ed43..46ebe4b9 100644
--- a/crates/oa-desktop/src/behavior/state_label_canvas_tests.rs
+++ b/crates/oa-desktop/src/behavior/state_label_canvas_tests.rs
@@ -323,3 +323,141 @@ fn state_multiline_label_group_preview_replaces_old_hit_rectangle_and_cancel_res
     );
     assert_eq!(f.project, before);
 }
+
+#[test]
+fn state_multiline_label_group_commit_matches_fixed_project_and_one_step_history() {
+    let (f, edge, _) = multiline_label_fixture();
+    let b = placement(&f, f.b);
+    let c = placement(&f, f.c);
+    let before = f.project.clone();
+    // Declare the complete expected model before driving input. No event, preview,
+    // movement planner or resulting document supplies the expected displacement.
+    let mut expected = before.clone();
+    for id in [b, c] {
+        let node = expected
+            .diagrams
+            .get_mut(&f.diagram)
+            .unwrap()
+            .nodes
+            .get_mut(&id)
+            .unwrap();
+        node.position.x += 40.;
+        node.position.y += 40.;
+    }
+    let original_route = before.diagrams[&f.diagram].routes[0].clone();
+    let mut document = Document::from_project(before.clone(), Default::default()).unwrap();
+    let original_source = document.bundle().clone();
+    let mut view_canvas = canvas(&f, Tool::Select, 0.75);
+    let selection = group_selection(&view_canvas, [Target::Placement(b), Target::Placement(c)]);
+    let snapshot = selection
+        .snapshot(selection_context(view_canvas.context))
+        .unwrap();
+    view_canvas.selection = Some(&selection);
+    view_canvas.selected = f.c;
+    let mut state = State::default();
+    let baseline = view_canvas.scene(&state).unwrap();
+    let baseline_label = &baseline.routed.edges[&edge].label;
+    assert_eq!(baseline_label.center, Position { x: 440., y: 260. });
+    // Explicit 0.75 scale: thirty screen pixels is the declared forty world
+    // units. The nonzero pan/origin and ordered pointer helpers stay in play.
+    let start = screen(&view_canvas, Point::new(780., 200.));
+    let end = start + Vector::new(30., 30.);
+    motion(&view_canvas, &mut state, start, end);
+    assert!(
+        input(
+            &view_canvas,
+            &mut state,
+            mouse::Event::ButtonPressed(mouse::Button::Left),
+            end
+        )
+        .is_none()
+    );
+    assert!(state.group.is_some());
+    motion(&view_canvas, &mut state, end, end);
+    let preview = view_canvas
+        .scene_with_bounds(&state, Some(bounds()))
+        .unwrap();
+    let preview_label = &preview.routed.edges[&edge].label;
+    assert_eq!(preview_label.center, Position { x: 480., y: 300. });
+    assert_eq!(
+        preview_label.bounds.position,
+        Position {
+            x: baseline_label.bounds.position.x + 40.,
+            y: baseline_label.bounds.position.y + 40.,
+        }
+    );
+    assert_eq!(preview_label.bounds.size, baseline_label.bounds.size);
+    assert_eq!(preview_label.state_layout, baseline_label.state_layout);
+    assert_eq!(
+        f.project, before,
+        "Preview must not author its derived label"
+    );
+    let event = input(
+        &view_canvas,
+        &mut state,
+        mouse::Event::ButtonReleased(mouse::Button::Left),
+        end,
+    )
+    .unwrap();
+    let Event::Selection(SelectionEvent::Move(actual_snapshot, delta)) = event else {
+        panic!("Expected a group movement event, got {event:?}");
+    };
+    assert_eq!(actual_snapshot, snapshot);
+    assert_eq!(delta, Position { x: 40., y: 40. });
+    assert!(state.group.is_none() && state.press.is_none());
+    assert!(
+        input(
+            &view_canvas,
+            &mut state,
+            mouse::Event::ButtonReleased(mouse::Button::Left),
+            end
+        )
+        .is_none()
+    );
+    // This is the same production snapshot-to-command boundary used by App's
+    // SelectionEvent::Move handler; App admission has its existing separate tests.
+    let ids = crate::app::multiselect::placements(&actual_snapshot).unwrap();
+    let command =
+        oa_core::diagram_edit::translate_placements(document.project(), f.diagram, &ids, delta)
+            .unwrap();
+    document.execute(command).unwrap();
+    assert_eq!(document.project(), &expected);
+    assert_eq!(
+        document.project().diagrams[&f.diagram].routes[0],
+        original_route,
+        "Authored fraction, offset, attachments and empty waypoints remain exact"
+    );
+    let committed = StateCanvas {
+        project: document.project(),
+        ..canvas(&f, Tool::Select, 0.75)
+    }
+    .scene(&State::default())
+    .unwrap();
+    assert_eq!(
+        committed.routed.edges[&edge].label, *preview_label,
+        "Measured settled label, including raw text and every line cell, matches preview"
+    );
+    let edited_source = document.bundle().clone();
+    assert_ne!(
+        edited_source, original_source,
+        "The group move is a real source edit"
+    );
+    assert!(document.undo());
+    assert_eq!(document.project(), &before);
+    assert_eq!(document.bundle(), &original_source);
+    assert!(
+        !document.undo(),
+        "One group release produces exactly one history entry"
+    );
+    assert!(document.redo());
+    assert_eq!(document.project(), &expected);
+    assert_eq!(document.bundle(), &edited_source);
+    assert!(!document.redo());
+    assert_eq!(
+        selection
+            .snapshot(selection_context(view_canvas.context))
+            .unwrap(),
+        snapshot
+    );
+    assert_eq!(f.project, before);
+}