diff --git a/crates/ui-egui/src/panels/timeline.rs b/crates/ui-egui/src/panels/timeline.rs
index f1d107d5e..ea18c7f1e 100644
--- a/crates/ui-egui/src/panels/timeline.rs
+++ b/crates/ui-egui/src/panels/timeline.rs
@@ -4533,542 +4533,4 @@ fn value_editor(
 }
 
 #[cfg(test)]
-mod tests {
-    use super::*;
-
-    /// Alt/Option-drag takes the same Project items `layer.replaceSource` does: compositions,
-    /// footage and solids, never folders, data files or 3D models.
-    #[test]
-    fn replace_source_takes_visual_items_only() {
-        use effectcraft_engine::color::Label;
-        use effectcraft_engine::project::{Comp, Footage, Project, Solid};
-        use effectcraft_engine::time::{FrameRate, Tick};
-        let mut p = Project::default();
-        let l = Label::None;
-        let comp = p.add_item("C", l, None, ItemKind::Comp(Comp::new(10, 10, FrameRate::FPS_30, Tick::from_seconds_f64(1.0)).into()));
-        let folder = p.add_item("F", l, None, ItemKind::Folder);
-        let still = p.add_item("S", l, None, ItemKind::Footage(Footage { kind: FootageKind::Still, ..Default::default() }));
-        let data = p.add_item("D", l, None, ItemKind::Footage(Footage { kind: FootageKind::Data, ..Default::default() }));
-        let model = p.add_item("M", l, None, ItemKind::Footage(Footage { kind: FootageKind::Model, ..Default::default() }));
-        let solid = p.add_item("So", l, None, ItemKind::Solid(Solid { color: [0.0; 3], width: 10, height: 10, pixel_aspect: 1.0 }));
-        for (id, ok) in [(comp, true), (still, true), (solid, true), (folder, false), (data, false), (model, false)] {
-            assert_eq!(replaceable_item(p.item(id).unwrap()), ok, "{id:?}");
-        }
-    }
-
-    /// Alt/Cmd-click twirls Audio's Waveform row (not in the property tree) with the rest.
-    #[test]
-    fn the_waveform_row_twirls_with_its_tree() {
-        let mut root = PropGroup::new(1, "", "");
-        let mut audio = PropGroup::new(2, "audio", "Audio");
-        audio.children.push(PropGroup::new(3, "x", "X").into());
-        root.children.push(audio.into());
-        let mut uids = vec![];
-        walk_groups(&root, &mut uids);
-        assert_eq!(uids, vec![2, WAVE_BIT | 2, 3]);
-        let mut uids = vec![];
-        walk_groups(find_group(&root, 2).unwrap(), &mut uids);
-        assert_eq!(uids, vec![WAVE_BIT | 2, 3]);
-    }
-
-    /// #710: with Time Display set to Frames the ruler labels are frame numbers (as under the
-    /// CTI, from Start Numbering Frames At); otherwise seconds:frames.
-    #[test]
-    fn ruler_labels_follow_the_time_display_style() {
-        use effectcraft_engine::project::{ProjectSettings, TimeDisplayStyle};
-        let mut st = ProjectSettings { time_display: TimeDisplayStyle::Timecode, frame_start: 0, ..ProjectSettings::default() };
-        assert_eq!(ruler_label(15, 30, &st), "00:15f");
-        assert_eq!(ruler_label(45, 30, &st), "01:15f");
-        assert_eq!(ruler_label(30 * 3600 + 31, 30, &st), "60:01:01f");
-        st.time_display = TimeDisplayStyle::Frames;
-        assert_eq!(ruler_label(0, 30, &st), "00000");
-        assert_eq!(ruler_label(45, 30, &st), "00045");
-        st.frame_start = 1;
-        assert_eq!(ruler_label(45, 30, &st), "00046");
-        assert_eq!(ruler_label(i64::MAX, 30, &st), format!("{:05}", i64::MAX));
-    }
-
-    /// #468: playback pages the view to the CTI; a scrub past either end scrolls that way.
-    #[test]
-    fn the_view_pages_to_the_cti() {
-        assert_eq!(page_to_cti(10.0, 5.0, 60.0, 12.0), 10.0, "in view: unchanged");
-        assert_eq!(page_to_cti(10.0, 5.0, 60.0, 16.0), 16.0, "past the right end: the page from the CTI");
-        assert_eq!(page_to_cti(10.0, 5.0, 60.0, 3.0), 3.0, "before the start");
-        assert_eq!(page_to_cti(10.0, 5.0, 60.0, 58.0), 55.0, "not past the comp's end");
-        assert_eq!(page_to_cti(10.0, 80.0, 60.0, 95.0), 0.0);
-        assert_eq!(page_to_cti(10.0, f64::NAN, 60.0, 95.0), 10.0);
-        assert_eq!(edge_scroll_speed_x(100.0, 500.0, 300.0), 0.0);
-        assert!(edge_scroll_speed_x(100.0, 500.0, 501.0) > 0.0 && edge_scroll_speed_x(100.0, 500.0, 99.0) < 0.0);
-        assert!(edge_scroll_speed_x(100.0, 500.0, 600.0) > edge_scroll_speed_x(100.0, 500.0, 520.0));
-    }
-
-    /// #864: picking only a mode in a layer's Track Matte menu sets a matte (the layer above);
-    /// it used to close the menu and change nothing.
-    #[test]
-    fn a_track_matte_mode_without_a_matte_takes_the_layer_above() {
-        let mut s = effectcraft_engine::Session::default();
-        s.execute("comp.new", json!({"name": "T", "width": 64, "height": 64, "duration": 1})).unwrap();
-        for name in ["Chain Bottom", "Matte", "Chain Top"] {
-            s.execute("layer.newSolid", json!({"name": name, "color": "#ffffff", "width": 64, "height": 64})).unwrap();
-        }
-        let find = |s: &effectcraft_engine::Session, n: &str| s.active_comp().unwrap().layers.iter().find(|l| l.name == n).unwrap().clone();
-        let (bottom, matte, top) = (find(&s, "Chain Bottom"), find(&s, "Matte"), find(&s, "Chain Top"));
-        let candidates = [top.id, matte.id];
-        let pick = |s: &mut effectcraft_engine::Session, name: &str, i: usize, choice: &str| {
-            let (id, params) = track_matte_pick(&find(s, name), &candidates, i, choice).expect("a menu item is an action");
-            s.execute(&id, params)
-        };
-        pick(&mut s, "Chain Bottom", 5, "Alpha Inverted Matte").unwrap();
-        let m = find(&s, "Chain Bottom").track_matte.expect("a matte");
-        assert_eq!((m.layer, m.kind), (matte.id, MatteKind::AlphaInverted));
-        assert!(!find(&s, "Matte").switches.video, "the matte layer is hidden");
-        // A mode change keeps the matte layer; a matte change keeps the mode.
-        pick(&mut s, "Chain Bottom", 6, "Luma Matte").unwrap();
-        assert_eq!(find(&s, "Chain Bottom").track_matte.map(|m| (m.layer, m.kind)), Some((matte.id, MatteKind::Luma)));
-        pick(&mut s, "Chain Bottom", 2, "1. Chain Top").unwrap();
-        assert_eq!(find(&s, "Chain Bottom").track_matte.map(|m| (m.layer, m.kind)), Some((top.id, MatteKind::Luma)));
-        assert!(s.undo());
-        assert_eq!(find(&s, "Chain Bottom").track_matte.map(|m| m.layer), Some(matte.id), "one undo step per pick");
-        // The top layer has nothing above it: an error for the status bar, not a silent no-op.
-        assert!(pick(&mut s, "Chain Top", 5, "Alpha Matte").is_err());
-        pick(&mut s, "Chain Bottom", 0, "No Track Matte").unwrap();
-        assert!(find(&s, "Chain Bottom").track_matte.is_none());
-        assert!(track_matte_pick(&bottom, &candidates, 1, "-").is_none(), "a separator does nothing");
-    }
-
-    /// #957: vector footage gets the Continuously Rasterize switch; raster footage does not.
-    #[test]
-    fn collapse_switch_shows_for_vector_footage_only() {
-        use effectcraft_engine::color::Label;
-        use effectcraft_engine::project::{Footage, ItemKind, Project};
-        let mut p = Project::default();
-        let mut layer_for = |name: &str, codec: &str| {
-            let footage = Footage { path: name.into(), codec: codec.into(), ..Default::default() };
-            let item = p.add_item(name, Label::SeaFoam, None, ItemKind::Footage(footage));
-            let comp = Comp::new(64, 36, effectcraft_engine::time::FrameRate::new(30, 1), Tick::from_seconds_f64(1.0));
-            effectcraft_engine::project::build::layer(&mut p, &comp, name, LayerSource::Footage { item }, (0, 0), None)
-        };
-        let svg = layer_for("logo.svg", "SVG");
-        let png = layer_for("photo.png", "PNG");
-        assert!(collapse_applies(&svg, &p));
-        assert!(!collapse_applies(&png, &p));
-    }
-
-    /// A comp with two solids; "Box" has an animated Position and a Gaussian Blur.
-    fn app() -> EffectcraftApp {
-        let mut s = effectcraft_engine::Session::default();
-        s.execute("comp.new", json!({"name": "T", "width": 320, "height": 180, "duration": 4})).unwrap();
-        s.execute("layer.newSolid", json!({"name": "Plate", "color": "#406080", "width": 320, "height": 180})).unwrap();
-        s.execute("layer.newSolid", json!({"name": "Box", "color": "#e04020", "width": 40, "height": 40})).unwrap();
-        let comp = s.active_comp().unwrap();
-        let bx = comp.layers.iter().find(|l| l.name == "Box").unwrap().id.0;
-        s.execute("layer.select", json!({"layers": [bx]})).unwrap();
-        s.execute("effect.apply", json!({"effect": "ec.blur.gaussian"})).unwrap();
-        let pos = s.active_comp().unwrap().layer(LayerId(bx)).unwrap().transform().unwrap().get("position").unwrap().uid;
-        s.execute("prop.toggleAnimation", json!({"layer": bx, "prop": pos})).unwrap();
-        EffectcraftApp::new(s)
-    }
-
-    fn labels(app: &EffectcraftApp) -> Vec<String> {
-        let comp = app.session.active_comp().unwrap().clone();
-        build_rows(app, &comp)
-            .into_iter()
-            .map(|r| {
-                let l = comp.layer(r.layer).unwrap();
-                match r.kind {
-                    RowKind::Layer => l.name.clone(),
-                    RowKind::Group { name, .. } => format!("{}>{name}", "  ".repeat(r.depth)),
-                    RowKind::Prop { uid } => format!("{}{}", "  ".repeat(r.depth), l.props.find(uid).unwrap().name),
-                    _ => "?".into(),
-                }
-            })
-            .collect()
-    }
-
-    #[test]
-    fn search_filters_layers_and_reveals_matching_properties() {
-        let mut app = app();
-        app.ui.timeline.search = "opac".into();
-        let rows = labels(&app);
-        // Both layers have Transform > Opacity; nothing else shows.
-        assert_eq!(rows.iter().filter(|r| r.trim() == "Opacity").count(), 2, "{rows:?}");
-        assert!(rows.iter().any(|r| r.trim() == ">Transform"), "{rows:?}");
-        assert!(!rows.iter().any(|r| r.trim() == "Position"), "{rows:?}");
-        // A layer name match shows the layer alone; a group match brings its contents.
-        app.ui.timeline.search = "plate".into();
-        assert_eq!(labels(&app), vec!["Plate".to_string()]);
-        app.ui.timeline.search = "GAUSSIAN".into();
-        let rows = labels(&app);
-        assert_eq!(rows[0], "Box");
-        assert!(rows.iter().any(|r| r.trim() == ">Effects") && rows.iter().any(|r| r.trim() == "Blurriness"), "{rows:?}");
-        assert!(!rows.contains(&"Plate".to_string()));
-        // Nothing matches → no rows.
-        app.ui.timeline.search = "zzz".into();
-        assert!(labels(&app).is_empty());
-        // Through the command.
-        let ctx = egui::Context::default();
-        crate::menus::invoke(&mut app, &ctx, "timeline.search", json!({"query": "scale"})).unwrap();
-        assert!(labels(&app).iter().any(|r| r.trim() == "Scale"));
-    }
-
-    /// A shape group's inner Contents (AE's elided `ADBE Vectors Group`) draws no row: the
-    /// search shows the full row hierarchy with the group's items — path, fill and Transform —
-    /// listing directly under the group, and the only "Contents" row the layer's own.
-    #[test]
-    fn shape_group_inner_contents_is_elided() {
-        let mut s = effectcraft_engine::Session::default();
-        s.execute("comp.new", json!({"name": "T", "width": 320, "height": 180, "duration": 4})).unwrap();
-        s.execute("layer.newShape", json!({"kind": "rect"})).unwrap();
-        let mut app = EffectcraftApp::new(s);
-        app.ui.timeline.search = "rect".into();
-        assert_eq!(
-            labels(&app),
-            [
-                "Shape Layer 1",
-                "  >Contents",
-                "    >Rectangle 1",
-                "      >Rectangle Path 1",
-                "        Size",
-                "        Position",
-                "        Roundness",
-                "      >Fill 1",
-                "        Composite",
-                "        Fill Rule",
-                "        Color",
-                "        Opacity",
-                "      >Transform",
-                "        Anchor Point",
-                "        Position",
-                "        Scale",
-                "        Skew",
-                "        Skew Axis",
-                "        Rotation",
-                "        Opacity",
-            ]
-            .iter()
-            .map(|r| r.to_string())
-            .collect::<Vec<_>>()
-        );
-    }
-
-    #[test]
-    fn columns_toggle_and_layout() {
-        let mut app = app();
-        let tl = &mut app.ui.timeline;
-        assert!(column_visible(tl, "switches") && !column_visible(tl, "comment") && !column_visible(tl, "modes"));
-        set_column(tl, "comment", true).unwrap();
-        set_column(tl, "stretch", true).unwrap();
-        set_column(tl, "keys", false).unwrap();
-        set_column(tl, "label", false).unwrap();
-        set_column(tl, "modes", true).unwrap();
-        assert!(tl.show_modes && column_visible(tl, "comment") && !column_visible(tl, "label"));
-        assert!(set_column(tl, "name", false).is_err());
-        assert!(set_column(tl, "bogus", true).is_err());
-        let vis = Vis::of(tl);
-        let cw = cols(0.0, 1400.0, vis);
-        // Hidden columns take no room; visible ones are in After Effects' order.
-        assert_eq!(cw.keys, cw.label);
-        assert_eq!(cw.label, cw.num);
-        assert!(cw.name < cw.comment && cw.comment < cw.switches && cw.switches < cw.mode && cw.parent < cw.stretch);
-        assert_eq!(column_at(&cw, cw.comment + 5.0), Some("comment"));
-        assert_eq!(column_at(&cw, cw.name + 5.0), Some("name"));
-        assert_eq!(column_at(&cw, cw.stretch + 5.0), Some("stretch"));
-        // Through the command (as agents do).
-        let ctx = egui::Context::default();
-        let r = crate::menus::invoke(&mut app, &ctx, "timeline.column", json!({"column": "duration"})).unwrap();
-        assert!(r["columns"].as_array().unwrap().iter().any(|c| c == "duration"));
-        crate::menus::invoke(&mut app, &ctx, "timeline.column", json!({"column": "duration", "visible": false})).unwrap();
-        assert!(!column_visible(&app.ui.timeline, "duration"));
-        crate::menus::invoke(&mut app, &ctx, "timeline.sourceName", json!({})).unwrap();
-        assert!(app.ui.timeline.source_name);
-    }
-
-    #[test]
-    fn reveal_keys_add_with_shift_and_uu_reveals_modified() {
-        let mut app = app();
-        let ctx = egui::Context::default();
-        crate::menus::invoke(&mut app, &ctx, "timeline.reveal.opacity", json!({})).unwrap();
-        assert_eq!(app.ui.timeline.reveal, vec!["opacity"]);
-        crate::menus::invoke(&mut app, &ctx, "timeline.revealAdd.scale", json!({})).unwrap();
-        crate::menus::invoke(&mut app, &ctx, "timeline.revealAdd.effects", json!({})).unwrap();
-        assert_eq!(app.ui.timeline.reveal, vec!["opacity", "scale", "effects"]);
-        let rows = labels(&app);
-        assert!(rows.iter().any(|r| r.trim() == "Scale") && rows.iter().any(|r| r.trim() == "Opacity"), "{rows:?}");
-        assert!(rows.iter().any(|r| r.trim() == ">Gaussian Blur"), "{rows:?}");
-        // Tree order: Scale before Opacity.
-        let si = rows.iter().position(|r| r.trim() == "Scale").unwrap();
-        let oi = rows.iter().position(|r| r.trim() == "Opacity").unwrap();
-        assert!(si < oi);
-        // Shift+S again removes Scale.
-        crate::menus::invoke(&mut app, &ctx, "timeline.revealAdd.scale", json!({})).unwrap();
-        assert_eq!(app.ui.timeline.reveal, vec!["opacity", "effects"]);
-        // U: keyframed properties (Position); UU (twice quickly): every modified property.
-        crate::menus::invoke(&mut app, &ctx, "anim.reveal", json!({"kind": "keyframes"})).unwrap();
-        let n_keys = app.ui.timeline.reveal_props.len();
-        assert_eq!(app.ui.timeline.reveal, vec!["props"]);
-        assert!(n_keys >= 1);
-        let bx = app.session.state.selected_layers[0].0;
-        app.session.execute("prop.set", json!({"layer": bx, "path": "effects/#1/blurriness", "value": 12})).unwrap();
-        crate::menus::invoke(&mut app, &ctx, "anim.reveal", json!({"kind": "keyframes"})).unwrap();
-        assert!(app.ui.timeline.reveal_props.len() > n_keys, "UU reveals modified properties too");
-    }
-
-    #[test]
-    fn scroll_to_time_centres_the_current_time_inside_the_comp() {
-        assert_eq!(centered_on(4.0, 10.0, 5.0), 3.0);
-        // Near the ends the view stops at the comp's start and end.
-        assert_eq!(centered_on(4.0, 10.0, 1.0), 0.0);
-        assert_eq!(centered_on(4.0, 10.0, 9.5), 6.0);
-        // A span longer than the comp, and bad numbers, start at zero.
-        assert_eq!(centered_on(20.0, 10.0, 5.0), 0.0);
-        assert_eq!(centered_on(f64::NAN, 10.0, 5.0), 0.0);
-    }
-
-    /// U and the other reveal shortcuts act on the selected layers only: other layers keep their
-    /// twirl state and their own reveal (#160).
-    #[test]
-    fn reveal_shortcuts_leave_unselected_layers_alone() {
-        let mut app = app();
-        let ctx = egui::Context::default();
-        let comp = app.session.active_comp().unwrap().clone();
-        let id = |n: &str| comp.layers.iter().find(|l| l.name == n).unwrap().id.0;
-        let (plate, bx) = (id("Plate"), id("Box"));
-        let select = |app: &mut EffectcraftApp, l: u64| app.session.execute("layer.select", json!({"layers": [l]})).unwrap();
-        // Plate shows Scale (S); then U on Box.
-        select(&mut app, plate);
-        crate::menus::invoke(&mut app, &ctx, "timeline.reveal.scale", json!({})).unwrap();
-        select(&mut app, bx);
-        crate::menus::invoke(&mut app, &ctx, "anim.reveal", json!({"kind": "keyframes"})).unwrap();
-        let tl = &app.ui.timeline;
-        assert!(tl.open_layers.contains(&plate) && tl.open_layers.contains(&bx), "{:?}", tl.open_layers);
-        assert_eq!(tl.layer_reveal.get(&plate), Some(&vec!["scale".to_string()]), "Plate keeps its reveal");
-        assert_eq!(tl.layer_reveal.get(&bx), Some(&vec!["props".to_string()]));
-        let rows = labels(&app);
-        let at = |n: &str| rows.iter().position(|r| r == n).unwrap();
-        assert_eq!(rows[at("Plate") + 1].trim(), "Scale", "{rows:?}");
-        assert_eq!(rows[at("Box") + 1].trim(), "Position", "{rows:?}");
-        // UU (modified): the effect's changed parameter only, under the effect twirled open.
-        // Then U later: Box shows its keyframed properties only again.
-        app.session.execute("prop.set", json!({"layer": bx, "path": "effects/#1/blurriness", "value": 12})).unwrap();
-        crate::menus::invoke(&mut app, &ctx, "anim.reveal", json!({"kind": "keyframes"})).unwrap();
-        let rows = labels(&app);
-        let fx = rows.iter().position(|r| r.trim().ends_with("Gaussian Blur")).unwrap_or_else(|| panic!("UU shows the effect: {rows:?}"));
-        assert_eq!(rows[fx + 1].trim(), "Blurriness", "{rows:?}");
-        assert!(!rows.iter().any(|r| r.trim() == "Blur Dimensions"), "unchanged parameters stay hidden: {rows:?}");
-        // Collapsed and expanded by hand, the effect shows all its parameters; UU filters again.
-        let fx_uid = app.session.active_comp().unwrap().layer(LayerId(bx)).unwrap().effects().unwrap().groups().next().unwrap().uid;
-        app.ui.timeline.toggle_group(bx, fx_uid);
-        assert!(!labels(&app).iter().any(|r| r.trim() == "Blurriness"), "collapsed");
-        app.ui.timeline.toggle_group(bx, fx_uid);
-        let rows = labels(&app);
-        assert!(rows.iter().any(|r| r.trim() == "Blurriness") && rows.iter().any(|r| r.trim() == "Blur Dimensions"), "{rows:?}");
-        app.last_reveal = Some(("keyframes".into(), f64::MAX));
-        crate::menus::invoke(&mut app, &ctx, "anim.reveal", json!({"kind": "keyframes"})).unwrap();
-        assert!(!labels(&app).iter().any(|r| r.trim() == "Blur Dimensions"), "UU again shows the changed ones only");
-        app.last_reveal = Some(("keyframes".into(), -10.0));
-        crate::menus::invoke(&mut app, &ctx, "anim.reveal", json!({"kind": "keyframes"})).unwrap();
-        app.last_reveal = Some(("keyframes".into(), -10.0));
-        crate::menus::invoke(&mut app, &ctx, "anim.reveal", json!({"kind": "keyframes"})).unwrap();
-        let rows = labels(&app);
-        assert!(!rows.iter().any(|r| r.trim() == ">Gaussian Blur") && rows.iter().any(|r| r.trim() == "Position"), "{rows:?}");
-        // U again on Box (later than a double press) hides only Box's.
-        app.last_reveal = Some(("keyframes".into(), -10.0));
-        crate::menus::invoke(&mut app, &ctx, "anim.reveal", json!({"kind": "keyframes"})).unwrap();
-        let tl = &app.ui.timeline;
-        assert!(!tl.open_layers.contains(&bx) && tl.open_layers.contains(&plate), "{:?}", tl.open_layers);
-        // A layer twirled open by hand shows its whole tree, whatever was revealed elsewhere.
-        app.session.execute("layer.select", json!({"layers": []})).unwrap();
-        app.ui.timeline.open_layers.insert(bx);
-        let rows = labels(&app);
-        assert!(rows.iter().any(|r| r.trim() == ">Transform"), "{rows:?}");
-    }
-
-    /// U and UU show Time Remap on a layer with time remapping enabled.
-    #[test]
-    fn u_and_uu_reveal_time_remap() {
-        let mut s = effectcraft_engine::Session::default();
-        let inner = s.execute("comp.new", json!({"name": "Inner", "width": 32, "height": 32, "duration": 2})).unwrap()["comp"].as_u64().unwrap();
-        s.execute("comp.new", json!({"name": "Main", "width": 64, "height": 64, "duration": 4})).unwrap();
-        let nested = s.execute("layer.addItem", json!({"item": inner})).unwrap()["layer"].as_u64().unwrap();
-        let mut app = EffectcraftApp::new(s);
-        let ctx = egui::Context::default();
-        crate::menus::invoke(&mut app, &ctx, "layer.enableTimeRemap", json!({"layers": [nested]})).unwrap();
-        app.session.execute("layer.select", json!({"layers": [nested]})).unwrap();
-        for uu in [false, true] {
-            app.ui.timeline.layer_reveal.clear();
-            app.last_reveal = uu.then(|| ("keyframes".into(), f64::MAX));
-            crate::menus::invoke(&mut app, &ctx, "anim.reveal", json!({"kind": "keyframes"})).unwrap();
-            assert_eq!(app.ui.timeline.layer_reveal.get(&nested), Some(&vec!["props".to_string()]), "UU: {uu}");
-            let rows = labels(&app);
-            let at = rows.iter().position(|r| r == "Inner").unwrap();
-            assert_eq!(rows[at + 1].trim(), "Time Remap", "UU: {uu}: {rows:?}");
-        }
-    }
-
-    /// U shows Time Remap while remapping is enabled even after its keys are deleted (#990):
-    /// enabling remapping is itself the modification.
-    #[test]
-    fn u_reveals_keyless_time_remap() {
-        let mut s = effectcraft_engine::Session::default();
-        let inner = s.execute("comp.new", json!({"name": "Inner", "width": 32, "height": 32, "duration": 2})).unwrap()["comp"].as_u64().unwrap();
-        s.execute("comp.new", json!({"name": "Main", "width": 64, "height": 64, "duration": 4})).unwrap();
-        let nested = s.execute("layer.addItem", json!({"item": inner})).unwrap()["layer"].as_u64().unwrap();
-        let mut app = EffectcraftApp::new(s);
-        let ctx = egui::Context::default();
-        crate::menus::invoke(&mut app, &ctx, "layer.enableTimeRemap", json!({"layers": [nested]})).unwrap();
-        let uid = app.session.active_comp().unwrap().layer(LayerId(nested)).unwrap().props.prop("timeRemap").unwrap().uid;
-        for _ in 0..2 {
-            let t = app.session.active_comp().unwrap().layer(LayerId(nested)).unwrap().props.prop("timeRemap").unwrap().keys[0].time.seconds();
-            app.session.execute("keys.select", json!({"keys": [{"layer": nested, "prop": uid, "time": t}]})).unwrap();
-            app.session.execute("edit.clear", json!({})).unwrap();
-        }
-        assert!(app.session.active_comp().unwrap().layer(LayerId(nested)).unwrap().props.prop("timeRemap").unwrap().keys.is_empty());
-        app.session.execute("layer.select", json!({"layers": [nested]})).unwrap();
-        crate::menus::invoke(&mut app, &ctx, "anim.reveal", json!({"kind": "keyframes"})).unwrap();
-        assert_eq!(app.ui.timeline.layer_reveal.get(&nested), Some(&vec!["props".to_string()]));
-        let rows = labels(&app);
-        let at = rows.iter().position(|r| r == "Inner").unwrap();
-        assert_eq!(rows[at + 1].trim(), "Time Remap", "{rows:?}");
-    }
-
-    /// Enabling time remapping twirls the layer open on Time Remap (#157); disabling it reveals
-    /// nothing.
-    #[test]
-    fn enabling_time_remapping_reveals_time_remap() {
-        let mut s = effectcraft_engine::Session::default();
-        let inner = s.execute("comp.new", json!({"name": "Inner", "width": 32, "height": 32, "duration": 2})).unwrap()["comp"].as_u64().unwrap();
-        s.execute("comp.new", json!({"name": "Main", "width": 64, "height": 64, "duration": 4})).unwrap();
-        s.execute("layer.newSolid", json!({"name": "Other"})).unwrap();
-        let nested = s.execute("layer.addItem", json!({"item": inner})).unwrap()["layer"].as_u64().unwrap();
-        let mut app = EffectcraftApp::new(s);
-        let ctx = egui::Context::default();
-        crate::menus::invoke(&mut app, &ctx, "layer.enableTimeRemap", json!({"layers": [nested]})).unwrap();
-        assert_eq!(app.ui.timeline.layer_reveal.get(&nested), Some(&vec!["timeRemap".to_string()]));
-        let rows = labels(&app);
-        let at = rows.iter().position(|r| r == "Inner").unwrap();
-        assert_eq!(rows[at + 1].trim(), "Time Remap", "{rows:?}");
-        // Through the selection (the Layer menu), turning it off again: nothing new is revealed.
-        app.session.execute("layer.select", json!({"layers": [nested]})).unwrap();
-        app.ui.timeline.layer_reveal.clear();
-        crate::menus::invoke(&mut app, &ctx, "layer.enableTimeRemap", json!({})).unwrap();
-        assert!(app.ui.timeline.layer_reveal.is_empty());
-    }
-
-    #[test]
-    fn cti_snaps_to_the_nearest_candidate() {
-        assert_eq!(snap_time(&[0.0, 1.0, 2.0], 1.04, 0.1), 1.0);
-        assert_eq!(snap_time(&[0.0, 1.0, 2.0], 1.5, 0.1), 1.5);
-        assert_eq!(snap_time(&[1.0, 1.1], 1.06, 0.1), 1.1);
-        let app = app();
-        let comp = app.session.active_comp().unwrap().clone();
-        let c = snap_candidates(&comp, &build_rows(&app, &comp));
-        assert!(c.contains(&comp.duration.seconds()) && c.contains(&0.0));
-    }
-
-    /// Every string drawn by one frame of `draw`.
-    fn drawn_text(mut draw: impl FnMut(&mut egui::Ui)) -> Vec<String> {
-        fn collect(shape: &egui::Shape, out: &mut Vec<String>) {
-            match shape {
-                egui::Shape::Text(t) => out.push(t.galley.text().to_string()),
-                egui::Shape::Vec(v) => v.iter().for_each(|s| collect(s, out)),
-                _ => {}
-            }
-        }
-        let ctx = egui::Context::default();
-        ctx.run_ui(Default::default(), |ui| draw(ui)).textures_delta.clear();
-        let mut frame = ctx.run_ui(Default::default(), |ui| draw(ui));
-        frame.textures_delta.clear();
-        let mut out = Vec::new();
-        frame.shapes.iter().for_each(|c| collect(&c.shape, &mut out));
-        out
-    }
-
-    /// #1308: the layer context menu draws its items in the interface language, from the menu
-    /// bar's rows for the same commands (whose ellipsis is `...`), and its Effects submenu draws
-    /// the categories the Effect menu does; the actions it records stay the same.
-    #[test]
-    fn the_layer_context_menu_draws_in_the_interface_language() {
-        let caps = LayerMenuCaps { vector: true, text: false, source: true };
-        let (mut auto, mut actions) = (crate::automation::Registry::default(), Vec::new());
-        crate::i18n::set_current("zh-hans");
-        let menu = drawn_text(|ui| layer_menu(ui, &[7], caps, (&mut auto, "t"), &mut actions));
-        let effects = drawn_text(|ui| effects_submenu(ui, &[7], &mut |_: &mut egui::Ui, _: &str, _: &str, _: serde_json::Value| {}));
-        crate::i18n::set_current("en");
-        let english = drawn_text(|ui| layer_menu(ui, &[7], caps, (&mut auto, "t"), &mut actions));
-        for label in ["新建", "图层设置...", "在项目中显示图层源", "从矢量图层创建形状", "预合成...", "重复", "拆分图层", "删除"]
-        {
-            assert!(menu.iter().any(|t| t == label), "{label} missing from {menu:?}");
-        }
-        assert!(!menu.iter().any(|t| t.is_ascii()), "English left in {menu:?}");
-        assert!(effects.iter().any(|t| t == "模糊和锐化"), "{effects:?}");
-        assert!(!effects.iter().any(|t| t == "Blur & Sharpen"), "{effects:?}");
-        for label in ["Layer Settings…", "Reveal Layer Source in Project", "Duplicate", "Delete"] {
-            assert!(english.iter().any(|t| t == label), "{label} missing from {english:?}");
-        }
-        assert!(actions.is_empty());
-    }
-
-    /// The property context menu draws its items in the interface language too: the commands the
-    /// menu bar has from its rows, Reset, Edit Value… and Remove Expression from the panel catalog.
-    /// The automation labels stay English.
-    #[test]
-    fn the_property_context_menu_draws_in_the_interface_language() {
-        let mut s = effectcraft_engine::Session::default();
-        s.execute("comp.new", json!({"name": "Main", "width": 64, "height": 64, "duration": 4})).unwrap();
-        let l = s.execute("layer.newSolid", json!({"name": "Plate", "color": "#406080"})).unwrap()["layer"].as_u64().unwrap();
-        let opacity = s.active_comp().unwrap().layer(LayerId(l)).unwrap().props.prop("transform/opacity").unwrap().uid;
-        s.execute("prop.setExpression", json!({"layer": l, "prop": opacity})).unwrap();
-        let comp = s.active_comp_id().unwrap();
-        let layer = s.active_comp().unwrap().layer(LayerId(l)).unwrap().clone();
-        let (position, opacity) = (layer.props.prop("transform/position").unwrap(), layer.props.prop("transform/opacity").unwrap());
-        let (mut auto, mut actions) = (crate::automation::Registry::default(), Vec::new());
-        let mut menu = |language| {
-            crate::i18n::set_current(language);
-            let mut drawn = drawn_text(|ui| prop_menu(ui, &mut auto, comp, &layer, position, &mut actions));
-            drawn.extend(drawn_text(|ui| prop_menu(ui, &mut auto, comp, &layer, opacity, &mut actions)));
-            drawn
-        };
-        let chinese = menu("zh-hans");
-        let english = menu("en");
-        for label in ["重置", "编辑值…", "单独尺寸", "添加表达式", "移除表达式", "向基本图形添加属性"] {
-            assert!(chinese.iter().any(|t| t == label), "{label} missing from {chinese:?}");
-        }
-        assert!(!chinese.iter().any(|t| t.is_ascii()), "English left in {chinese:?}");
-        for label in ["Reset", "Edit Value…", "Separate Dimensions", "Remove Expression", "Add Property to Essential Graphics"] {
-            assert!(english.iter().any(|t| t == label), "{label} missing from {english:?}");
-        }
-        assert!(auto.elements.iter().any(|e| e.label == "Remove Expression"), "the automation label stays English");
-        assert!(actions.is_empty());
-    }
-
-    /// UI fidelity (M13.5): compact After Effects-like rows and muted label-coloured bars.
-    #[test]
-    fn rows_and_bars_follow_after_effects_proportions() {
-        let t = crate::theme::Tokens::for_kind(crate::theme::ThemeKind::Dark);
-        assert_eq!(t.row_h, 19.0);
-        let red = t.label(effectcraft_engine::color::Label::Red);
-        let bar = bar_color(red, false);
-        // Muted: darker and less saturated than the label, still reddish.
-        assert!(bar.r() < red.r() && bar.r() > bar.g() + 30 && bar.g() >= red.g().min(0x3a) - 1);
-        let sel = bar_color(red, true);
-        assert!(sel.r() > bar.r());
-    }
-
-    #[test]
-    fn disk_bar_range_covers_partial_frames() {
-        let clip = Rect::from_min_max(pos2(0.0, 0.0), pos2(2.0, 1.0));
-        let tm = TMap { x0: 0.0, start: 10.25, pps: 1.0 };
-        assert_eq!(disk_bar_range(&tm, clip, 1.0, 100), 10..13);
-
-        let exact = TMap { start: 10.0, ..tm };
-        assert_eq!(disk_bar_range(&exact, clip, 1.0, 100), 10..12);
-        let off_comp = TMap { start: 200.0, ..tm };
-        assert_eq!(disk_bar_range(&off_comp, clip, 1.0, 100), 100..100);
-        assert_eq!(disk_bar_range(&tm, clip, f64::NAN, 100), 0..0);
-        assert_eq!(disk_bar_range(&TMap { pps: 0.0, ..tm }, clip, 1.0, 100), 0..0);
-        assert_eq!(disk_bar_range(&TMap { start: f64::NAN, ..tm }, clip, 1.0, 100), 0..0);
-        assert_eq!(disk_bar_range(&tm, Rect::from_min_max(pos2(2.0, 0.0), pos2(2.0, 1.0)), 1.0, 100), 0..0);
-        let above_limit = TMap { start: 100_001.0, ..tm };
-        assert_eq!(disk_bar_range(&above_limit, clip, 1.0, i64::MAX), 100_000..100_000);
-    }
-}
+mod tests;
diff --git a/crates/ui-egui/src/panels/timeline/tests.rs b/crates/ui-egui/src/panels/timeline/tests.rs
new file mode 100644
index 000000000..0355ea5ed
--- /dev/null
+++ b/crates/ui-egui/src/panels/timeline/tests.rs
@@ -0,0 +1,537 @@
+use super::*;
+
+/// Alt/Option-drag takes the same Project items `layer.replaceSource` does: compositions,
+/// footage and solids, never folders, data files or 3D models.
+#[test]
+fn replace_source_takes_visual_items_only() {
+    use effectcraft_engine::color::Label;
+    use effectcraft_engine::project::{Comp, Footage, Project, Solid};
+    use effectcraft_engine::time::{FrameRate, Tick};
+    let mut p = Project::default();
+    let l = Label::None;
+    let comp = p.add_item("C", l, None, ItemKind::Comp(Comp::new(10, 10, FrameRate::FPS_30, Tick::from_seconds_f64(1.0)).into()));
+    let folder = p.add_item("F", l, None, ItemKind::Folder);
+    let still = p.add_item("S", l, None, ItemKind::Footage(Footage { kind: FootageKind::Still, ..Default::default() }));
+    let data = p.add_item("D", l, None, ItemKind::Footage(Footage { kind: FootageKind::Data, ..Default::default() }));
+    let model = p.add_item("M", l, None, ItemKind::Footage(Footage { kind: FootageKind::Model, ..Default::default() }));
+    let solid = p.add_item("So", l, None, ItemKind::Solid(Solid { color: [0.0; 3], width: 10, height: 10, pixel_aspect: 1.0 }));
+    for (id, ok) in [(comp, true), (still, true), (solid, true), (folder, false), (data, false), (model, false)] {
+        assert_eq!(replaceable_item(p.item(id).unwrap()), ok, "{id:?}");
+    }
+}
+
+/// Alt/Cmd-click twirls Audio's Waveform row (not in the property tree) with the rest.
+#[test]
+fn the_waveform_row_twirls_with_its_tree() {
+    let mut root = PropGroup::new(1, "", "");
+    let mut audio = PropGroup::new(2, "audio", "Audio");
+    audio.children.push(PropGroup::new(3, "x", "X").into());
+    root.children.push(audio.into());
+    let mut uids = vec![];
+    walk_groups(&root, &mut uids);
+    assert_eq!(uids, vec![2, WAVE_BIT | 2, 3]);
+    let mut uids = vec![];
+    walk_groups(find_group(&root, 2).unwrap(), &mut uids);
+    assert_eq!(uids, vec![WAVE_BIT | 2, 3]);
+}
+
+/// #710: with Time Display set to Frames the ruler labels are frame numbers (as under the
+/// CTI, from Start Numbering Frames At); otherwise seconds:frames.
+#[test]
+fn ruler_labels_follow_the_time_display_style() {
+    use effectcraft_engine::project::{ProjectSettings, TimeDisplayStyle};
+    let mut st = ProjectSettings { time_display: TimeDisplayStyle::Timecode, frame_start: 0, ..ProjectSettings::default() };
+    assert_eq!(ruler_label(15, 30, &st), "00:15f");
+    assert_eq!(ruler_label(45, 30, &st), "01:15f");
+    assert_eq!(ruler_label(30 * 3600 + 31, 30, &st), "60:01:01f");
+    st.time_display = TimeDisplayStyle::Frames;
+    assert_eq!(ruler_label(0, 30, &st), "00000");
+    assert_eq!(ruler_label(45, 30, &st), "00045");
+    st.frame_start = 1;
+    assert_eq!(ruler_label(45, 30, &st), "00046");
+    assert_eq!(ruler_label(i64::MAX, 30, &st), format!("{:05}", i64::MAX));
+}
+
+/// #468: playback pages the view to the CTI; a scrub past either end scrolls that way.
+#[test]
+fn the_view_pages_to_the_cti() {
+    assert_eq!(page_to_cti(10.0, 5.0, 60.0, 12.0), 10.0, "in view: unchanged");
+    assert_eq!(page_to_cti(10.0, 5.0, 60.0, 16.0), 16.0, "past the right end: the page from the CTI");
+    assert_eq!(page_to_cti(10.0, 5.0, 60.0, 3.0), 3.0, "before the start");
+    assert_eq!(page_to_cti(10.0, 5.0, 60.0, 58.0), 55.0, "not past the comp's end");
+    assert_eq!(page_to_cti(10.0, 80.0, 60.0, 95.0), 0.0);
+    assert_eq!(page_to_cti(10.0, f64::NAN, 60.0, 95.0), 10.0);
+    assert_eq!(edge_scroll_speed_x(100.0, 500.0, 300.0), 0.0);
+    assert!(edge_scroll_speed_x(100.0, 500.0, 501.0) > 0.0 && edge_scroll_speed_x(100.0, 500.0, 99.0) < 0.0);
+    assert!(edge_scroll_speed_x(100.0, 500.0, 600.0) > edge_scroll_speed_x(100.0, 500.0, 520.0));
+}
+
+/// #864: picking only a mode in a layer's Track Matte menu sets a matte (the layer above);
+/// it used to close the menu and change nothing.
+#[test]
+fn a_track_matte_mode_without_a_matte_takes_the_layer_above() {
+    let mut s = effectcraft_engine::Session::default();
+    s.execute("comp.new", json!({"name": "T", "width": 64, "height": 64, "duration": 1})).unwrap();
+    for name in ["Chain Bottom", "Matte", "Chain Top"] {
+        s.execute("layer.newSolid", json!({"name": name, "color": "#ffffff", "width": 64, "height": 64})).unwrap();
+    }
+    let find = |s: &effectcraft_engine::Session, n: &str| s.active_comp().unwrap().layers.iter().find(|l| l.name == n).unwrap().clone();
+    let (bottom, matte, top) = (find(&s, "Chain Bottom"), find(&s, "Matte"), find(&s, "Chain Top"));
+    let candidates = [top.id, matte.id];
+    let pick = |s: &mut effectcraft_engine::Session, name: &str, i: usize, choice: &str| {
+        let (id, params) = track_matte_pick(&find(s, name), &candidates, i, choice).expect("a menu item is an action");
+        s.execute(&id, params)
+    };
+    pick(&mut s, "Chain Bottom", 5, "Alpha Inverted Matte").unwrap();
+    let m = find(&s, "Chain Bottom").track_matte.expect("a matte");
+    assert_eq!((m.layer, m.kind), (matte.id, MatteKind::AlphaInverted));
+    assert!(!find(&s, "Matte").switches.video, "the matte layer is hidden");
+    // A mode change keeps the matte layer; a matte change keeps the mode.
+    pick(&mut s, "Chain Bottom", 6, "Luma Matte").unwrap();
+    assert_eq!(find(&s, "Chain Bottom").track_matte.map(|m| (m.layer, m.kind)), Some((matte.id, MatteKind::Luma)));
+    pick(&mut s, "Chain Bottom", 2, "1. Chain Top").unwrap();
+    assert_eq!(find(&s, "Chain Bottom").track_matte.map(|m| (m.layer, m.kind)), Some((top.id, MatteKind::Luma)));
+    assert!(s.undo());
+    assert_eq!(find(&s, "Chain Bottom").track_matte.map(|m| m.layer), Some(matte.id), "one undo step per pick");
+    // The top layer has nothing above it: an error for the status bar, not a silent no-op.
+    assert!(pick(&mut s, "Chain Top", 5, "Alpha Matte").is_err());
+    pick(&mut s, "Chain Bottom", 0, "No Track Matte").unwrap();
+    assert!(find(&s, "Chain Bottom").track_matte.is_none());
+    assert!(track_matte_pick(&bottom, &candidates, 1, "-").is_none(), "a separator does nothing");
+}
+
+/// #957: vector footage gets the Continuously Rasterize switch; raster footage does not.
+#[test]
+fn collapse_switch_shows_for_vector_footage_only() {
+    use effectcraft_engine::color::Label;
+    use effectcraft_engine::project::{Footage, ItemKind, Project};
+    let mut p = Project::default();
+    let mut layer_for = |name: &str, codec: &str| {
+        let footage = Footage { path: name.into(), codec: codec.into(), ..Default::default() };
+        let item = p.add_item(name, Label::SeaFoam, None, ItemKind::Footage(footage));
+        let comp = Comp::new(64, 36, effectcraft_engine::time::FrameRate::new(30, 1), Tick::from_seconds_f64(1.0));
+        effectcraft_engine::project::build::layer(&mut p, &comp, name, LayerSource::Footage { item }, (0, 0), None)
+    };
+    let svg = layer_for("logo.svg", "SVG");
+    let png = layer_for("photo.png", "PNG");
+    assert!(collapse_applies(&svg, &p));
+    assert!(!collapse_applies(&png, &p));
+}
+
+/// A comp with two solids; "Box" has an animated Position and a Gaussian Blur.
+fn app() -> EffectcraftApp {
+    let mut s = effectcraft_engine::Session::default();
+    s.execute("comp.new", json!({"name": "T", "width": 320, "height": 180, "duration": 4})).unwrap();
+    s.execute("layer.newSolid", json!({"name": "Plate", "color": "#406080", "width": 320, "height": 180})).unwrap();
+    s.execute("layer.newSolid", json!({"name": "Box", "color": "#e04020", "width": 40, "height": 40})).unwrap();
+    let comp = s.active_comp().unwrap();
+    let bx = comp.layers.iter().find(|l| l.name == "Box").unwrap().id.0;
+    s.execute("layer.select", json!({"layers": [bx]})).unwrap();
+    s.execute("effect.apply", json!({"effect": "ec.blur.gaussian"})).unwrap();
+    let pos = s.active_comp().unwrap().layer(LayerId(bx)).unwrap().transform().unwrap().get("position").unwrap().uid;
+    s.execute("prop.toggleAnimation", json!({"layer": bx, "prop": pos})).unwrap();
+    EffectcraftApp::new(s)
+}
+
+fn labels(app: &EffectcraftApp) -> Vec<String> {
+    let comp = app.session.active_comp().unwrap().clone();
+    build_rows(app, &comp)
+        .into_iter()
+        .map(|r| {
+            let l = comp.layer(r.layer).unwrap();
+            match r.kind {
+                RowKind::Layer => l.name.clone(),
+                RowKind::Group { name, .. } => format!("{}>{name}", "  ".repeat(r.depth)),
+                RowKind::Prop { uid } => format!("{}{}", "  ".repeat(r.depth), l.props.find(uid).unwrap().name),
+                _ => "?".into(),
+            }
+        })
+        .collect()
+}
+
+#[test]
+fn search_filters_layers_and_reveals_matching_properties() {
+    let mut app = app();
+    app.ui.timeline.search = "opac".into();
+    let rows = labels(&app);
+    // Both layers have Transform > Opacity; nothing else shows.
+    assert_eq!(rows.iter().filter(|r| r.trim() == "Opacity").count(), 2, "{rows:?}");
+    assert!(rows.iter().any(|r| r.trim() == ">Transform"), "{rows:?}");
+    assert!(!rows.iter().any(|r| r.trim() == "Position"), "{rows:?}");
+    // A layer name match shows the layer alone; a group match brings its contents.
+    app.ui.timeline.search = "plate".into();
+    assert_eq!(labels(&app), vec!["Plate".to_string()]);
+    app.ui.timeline.search = "GAUSSIAN".into();
+    let rows = labels(&app);
+    assert_eq!(rows[0], "Box");
+    assert!(rows.iter().any(|r| r.trim() == ">Effects") && rows.iter().any(|r| r.trim() == "Blurriness"), "{rows:?}");
+    assert!(!rows.contains(&"Plate".to_string()));
+    // Nothing matches → no rows.
+    app.ui.timeline.search = "zzz".into();
+    assert!(labels(&app).is_empty());
+    // Through the command.
+    let ctx = egui::Context::default();
+    crate::menus::invoke(&mut app, &ctx, "timeline.search", json!({"query": "scale"})).unwrap();
+    assert!(labels(&app).iter().any(|r| r.trim() == "Scale"));
+}
+
+/// A shape group's inner Contents (AE's elided `ADBE Vectors Group`) draws no row: the
+/// search shows the full row hierarchy with the group's items — path, fill and Transform —
+/// listing directly under the group, and the only "Contents" row the layer's own.
+#[test]
+fn shape_group_inner_contents_is_elided() {
+    let mut s = effectcraft_engine::Session::default();
+    s.execute("comp.new", json!({"name": "T", "width": 320, "height": 180, "duration": 4})).unwrap();
+    s.execute("layer.newShape", json!({"kind": "rect"})).unwrap();
+    let mut app = EffectcraftApp::new(s);
+    app.ui.timeline.search = "rect".into();
+    assert_eq!(
+        labels(&app),
+        [
+            "Shape Layer 1",
+            "  >Contents",
+            "    >Rectangle 1",
+            "      >Rectangle Path 1",
+            "        Size",
+            "        Position",
+            "        Roundness",
+            "      >Fill 1",
+            "        Composite",
+            "        Fill Rule",
+            "        Color",
+            "        Opacity",
+            "      >Transform",
+            "        Anchor Point",
+            "        Position",
+            "        Scale",
+            "        Skew",
+            "        Skew Axis",
+            "        Rotation",
+            "        Opacity",
+        ]
+        .iter()
+        .map(|r| r.to_string())
+        .collect::<Vec<_>>()
+    );
+}
+
+#[test]
+fn columns_toggle_and_layout() {
+    let mut app = app();
+    let tl = &mut app.ui.timeline;
+    assert!(column_visible(tl, "switches") && !column_visible(tl, "comment") && !column_visible(tl, "modes"));
+    set_column(tl, "comment", true).unwrap();
+    set_column(tl, "stretch", true).unwrap();
+    set_column(tl, "keys", false).unwrap();
+    set_column(tl, "label", false).unwrap();
+    set_column(tl, "modes", true).unwrap();
+    assert!(tl.show_modes && column_visible(tl, "comment") && !column_visible(tl, "label"));
+    assert!(set_column(tl, "name", false).is_err());
+    assert!(set_column(tl, "bogus", true).is_err());
+    let vis = Vis::of(tl);
+    let cw = cols(0.0, 1400.0, vis);
+    // Hidden columns take no room; visible ones are in After Effects' order.
+    assert_eq!(cw.keys, cw.label);
+    assert_eq!(cw.label, cw.num);
+    assert!(cw.name < cw.comment && cw.comment < cw.switches && cw.switches < cw.mode && cw.parent < cw.stretch);
+    assert_eq!(column_at(&cw, cw.comment + 5.0), Some("comment"));
+    assert_eq!(column_at(&cw, cw.name + 5.0), Some("name"));
+    assert_eq!(column_at(&cw, cw.stretch + 5.0), Some("stretch"));
+    // Through the command (as agents do).
+    let ctx = egui::Context::default();
+    let r = crate::menus::invoke(&mut app, &ctx, "timeline.column", json!({"column": "duration"})).unwrap();
+    assert!(r["columns"].as_array().unwrap().iter().any(|c| c == "duration"));
+    crate::menus::invoke(&mut app, &ctx, "timeline.column", json!({"column": "duration", "visible": false})).unwrap();
+    assert!(!column_visible(&app.ui.timeline, "duration"));
+    crate::menus::invoke(&mut app, &ctx, "timeline.sourceName", json!({})).unwrap();
+    assert!(app.ui.timeline.source_name);
+}
+
+#[test]
+fn reveal_keys_add_with_shift_and_uu_reveals_modified() {
+    let mut app = app();
+    let ctx = egui::Context::default();
+    crate::menus::invoke(&mut app, &ctx, "timeline.reveal.opacity", json!({})).unwrap();
+    assert_eq!(app.ui.timeline.reveal, vec!["opacity"]);
+    crate::menus::invoke(&mut app, &ctx, "timeline.revealAdd.scale", json!({})).unwrap();
+    crate::menus::invoke(&mut app, &ctx, "timeline.revealAdd.effects", json!({})).unwrap();
+    assert_eq!(app.ui.timeline.reveal, vec!["opacity", "scale", "effects"]);
+    let rows = labels(&app);
+    assert!(rows.iter().any(|r| r.trim() == "Scale") && rows.iter().any(|r| r.trim() == "Opacity"), "{rows:?}");
+    assert!(rows.iter().any(|r| r.trim() == ">Gaussian Blur"), "{rows:?}");
+    // Tree order: Scale before Opacity.
+    let si = rows.iter().position(|r| r.trim() == "Scale").unwrap();
+    let oi = rows.iter().position(|r| r.trim() == "Opacity").unwrap();
+    assert!(si < oi);
+    // Shift+S again removes Scale.
+    crate::menus::invoke(&mut app, &ctx, "timeline.revealAdd.scale", json!({})).unwrap();
+    assert_eq!(app.ui.timeline.reveal, vec!["opacity", "effects"]);
+    // U: keyframed properties (Position); UU (twice quickly): every modified property.
+    crate::menus::invoke(&mut app, &ctx, "anim.reveal", json!({"kind": "keyframes"})).unwrap();
+    let n_keys = app.ui.timeline.reveal_props.len();
+    assert_eq!(app.ui.timeline.reveal, vec!["props"]);
+    assert!(n_keys >= 1);
+    let bx = app.session.state.selected_layers[0].0;
+    app.session.execute("prop.set", json!({"layer": bx, "path": "effects/#1/blurriness", "value": 12})).unwrap();
+    crate::menus::invoke(&mut app, &ctx, "anim.reveal", json!({"kind": "keyframes"})).unwrap();
+    assert!(app.ui.timeline.reveal_props.len() > n_keys, "UU reveals modified properties too");
+}
+
+#[test]
+fn scroll_to_time_centres_the_current_time_inside_the_comp() {
+    assert_eq!(centered_on(4.0, 10.0, 5.0), 3.0);
+    // Near the ends the view stops at the comp's start and end.
+    assert_eq!(centered_on(4.0, 10.0, 1.0), 0.0);
+    assert_eq!(centered_on(4.0, 10.0, 9.5), 6.0);
+    // A span longer than the comp, and bad numbers, start at zero.
+    assert_eq!(centered_on(20.0, 10.0, 5.0), 0.0);
+    assert_eq!(centered_on(f64::NAN, 10.0, 5.0), 0.0);
+}
+
+/// U and the other reveal shortcuts act on the selected layers only: other layers keep their
+/// twirl state and their own reveal (#160).
+#[test]
+fn reveal_shortcuts_leave_unselected_layers_alone() {
+    let mut app = app();
+    let ctx = egui::Context::default();
+    let comp = app.session.active_comp().unwrap().clone();
+    let id = |n: &str| comp.layers.iter().find(|l| l.name == n).unwrap().id.0;
+    let (plate, bx) = (id("Plate"), id("Box"));
+    let select = |app: &mut EffectcraftApp, l: u64| app.session.execute("layer.select", json!({"layers": [l]})).unwrap();
+    // Plate shows Scale (S); then U on Box.
+    select(&mut app, plate);
+    crate::menus::invoke(&mut app, &ctx, "timeline.reveal.scale", json!({})).unwrap();
+    select(&mut app, bx);
+    crate::menus::invoke(&mut app, &ctx, "anim.reveal", json!({"kind": "keyframes"})).unwrap();
+    let tl = &app.ui.timeline;
+    assert!(tl.open_layers.contains(&plate) && tl.open_layers.contains(&bx), "{:?}", tl.open_layers);
+    assert_eq!(tl.layer_reveal.get(&plate), Some(&vec!["scale".to_string()]), "Plate keeps its reveal");
+    assert_eq!(tl.layer_reveal.get(&bx), Some(&vec!["props".to_string()]));
+    let rows = labels(&app);
+    let at = |n: &str| rows.iter().position(|r| r == n).unwrap();
+    assert_eq!(rows[at("Plate") + 1].trim(), "Scale", "{rows:?}");
+    assert_eq!(rows[at("Box") + 1].trim(), "Position", "{rows:?}");
+    // UU (modified): the effect's changed parameter only, under the effect twirled open.
+    // Then U later: Box shows its keyframed properties only again.
+    app.session.execute("prop.set", json!({"layer": bx, "path": "effects/#1/blurriness", "value": 12})).unwrap();
+    crate::menus::invoke(&mut app, &ctx, "anim.reveal", json!({"kind": "keyframes"})).unwrap();
+    let rows = labels(&app);
+    let fx = rows.iter().position(|r| r.trim().ends_with("Gaussian Blur")).unwrap_or_else(|| panic!("UU shows the effect: {rows:?}"));
+    assert_eq!(rows[fx + 1].trim(), "Blurriness", "{rows:?}");
+    assert!(!rows.iter().any(|r| r.trim() == "Blur Dimensions"), "unchanged parameters stay hidden: {rows:?}");
+    // Collapsed and expanded by hand, the effect shows all its parameters; UU filters again.
+    let fx_uid = app.session.active_comp().unwrap().layer(LayerId(bx)).unwrap().effects().unwrap().groups().next().unwrap().uid;
+    app.ui.timeline.toggle_group(bx, fx_uid);
+    assert!(!labels(&app).iter().any(|r| r.trim() == "Blurriness"), "collapsed");
+    app.ui.timeline.toggle_group(bx, fx_uid);
+    let rows = labels(&app);
+    assert!(rows.iter().any(|r| r.trim() == "Blurriness") && rows.iter().any(|r| r.trim() == "Blur Dimensions"), "{rows:?}");
+    app.last_reveal = Some(("keyframes".into(), f64::MAX));
+    crate::menus::invoke(&mut app, &ctx, "anim.reveal", json!({"kind": "keyframes"})).unwrap();
+    assert!(!labels(&app).iter().any(|r| r.trim() == "Blur Dimensions"), "UU again shows the changed ones only");
+    app.last_reveal = Some(("keyframes".into(), -10.0));
+    crate::menus::invoke(&mut app, &ctx, "anim.reveal", json!({"kind": "keyframes"})).unwrap();
+    app.last_reveal = Some(("keyframes".into(), -10.0));
+    crate::menus::invoke(&mut app, &ctx, "anim.reveal", json!({"kind": "keyframes"})).unwrap();
+    let rows = labels(&app);
+    assert!(!rows.iter().any(|r| r.trim() == ">Gaussian Blur") && rows.iter().any(|r| r.trim() == "Position"), "{rows:?}");
+    // U again on Box (later than a double press) hides only Box's.
+    app.last_reveal = Some(("keyframes".into(), -10.0));
+    crate::menus::invoke(&mut app, &ctx, "anim.reveal", json!({"kind": "keyframes"})).unwrap();
+    let tl = &app.ui.timeline;
+    assert!(!tl.open_layers.contains(&bx) && tl.open_layers.contains(&plate), "{:?}", tl.open_layers);
+    // A layer twirled open by hand shows its whole tree, whatever was revealed elsewhere.
+    app.session.execute("layer.select", json!({"layers": []})).unwrap();
+    app.ui.timeline.open_layers.insert(bx);
+    let rows = labels(&app);
+    assert!(rows.iter().any(|r| r.trim() == ">Transform"), "{rows:?}");
+}
+
+/// U and UU show Time Remap on a layer with time remapping enabled.
+#[test]
+fn u_and_uu_reveal_time_remap() {
+    let mut s = effectcraft_engine::Session::default();
+    let inner = s.execute("comp.new", json!({"name": "Inner", "width": 32, "height": 32, "duration": 2})).unwrap()["comp"].as_u64().unwrap();
+    s.execute("comp.new", json!({"name": "Main", "width": 64, "height": 64, "duration": 4})).unwrap();
+    let nested = s.execute("layer.addItem", json!({"item": inner})).unwrap()["layer"].as_u64().unwrap();
+    let mut app = EffectcraftApp::new(s);
+    let ctx = egui::Context::default();
+    crate::menus::invoke(&mut app, &ctx, "layer.enableTimeRemap", json!({"layers": [nested]})).unwrap();
+    app.session.execute("layer.select", json!({"layers": [nested]})).unwrap();
+    for uu in [false, true] {
+        app.ui.timeline.layer_reveal.clear();
+        app.last_reveal = uu.then(|| ("keyframes".into(), f64::MAX));
+        crate::menus::invoke(&mut app, &ctx, "anim.reveal", json!({"kind": "keyframes"})).unwrap();
+        assert_eq!(app.ui.timeline.layer_reveal.get(&nested), Some(&vec!["props".to_string()]), "UU: {uu}");
+        let rows = labels(&app);
+        let at = rows.iter().position(|r| r == "Inner").unwrap();
+        assert_eq!(rows[at + 1].trim(), "Time Remap", "UU: {uu}: {rows:?}");
+    }
+}
+
+/// U shows Time Remap while remapping is enabled even after its keys are deleted (#990):
+/// enabling remapping is itself the modification.
+#[test]
+fn u_reveals_keyless_time_remap() {
+    let mut s = effectcraft_engine::Session::default();
+    let inner = s.execute("comp.new", json!({"name": "Inner", "width": 32, "height": 32, "duration": 2})).unwrap()["comp"].as_u64().unwrap();
+    s.execute("comp.new", json!({"name": "Main", "width": 64, "height": 64, "duration": 4})).unwrap();
+    let nested = s.execute("layer.addItem", json!({"item": inner})).unwrap()["layer"].as_u64().unwrap();
+    let mut app = EffectcraftApp::new(s);
+    let ctx = egui::Context::default();
+    crate::menus::invoke(&mut app, &ctx, "layer.enableTimeRemap", json!({"layers": [nested]})).unwrap();
+    let uid = app.session.active_comp().unwrap().layer(LayerId(nested)).unwrap().props.prop("timeRemap").unwrap().uid;
+    for _ in 0..2 {
+        let t = app.session.active_comp().unwrap().layer(LayerId(nested)).unwrap().props.prop("timeRemap").unwrap().keys[0].time.seconds();
+        app.session.execute("keys.select", json!({"keys": [{"layer": nested, "prop": uid, "time": t}]})).unwrap();
+        app.session.execute("edit.clear", json!({})).unwrap();
+    }
+    assert!(app.session.active_comp().unwrap().layer(LayerId(nested)).unwrap().props.prop("timeRemap").unwrap().keys.is_empty());
+    app.session.execute("layer.select", json!({"layers": [nested]})).unwrap();
+    crate::menus::invoke(&mut app, &ctx, "anim.reveal", json!({"kind": "keyframes"})).unwrap();
+    assert_eq!(app.ui.timeline.layer_reveal.get(&nested), Some(&vec!["props".to_string()]));
+    let rows = labels(&app);
+    let at = rows.iter().position(|r| r == "Inner").unwrap();
+    assert_eq!(rows[at + 1].trim(), "Time Remap", "{rows:?}");
+}
+
+/// Enabling time remapping twirls the layer open on Time Remap (#157); disabling it reveals
+/// nothing.
+#[test]
+fn enabling_time_remapping_reveals_time_remap() {
+    let mut s = effectcraft_engine::Session::default();
+    let inner = s.execute("comp.new", json!({"name": "Inner", "width": 32, "height": 32, "duration": 2})).unwrap()["comp"].as_u64().unwrap();
+    s.execute("comp.new", json!({"name": "Main", "width": 64, "height": 64, "duration": 4})).unwrap();
+    s.execute("layer.newSolid", json!({"name": "Other"})).unwrap();
+    let nested = s.execute("layer.addItem", json!({"item": inner})).unwrap()["layer"].as_u64().unwrap();
+    let mut app = EffectcraftApp::new(s);
+    let ctx = egui::Context::default();
+    crate::menus::invoke(&mut app, &ctx, "layer.enableTimeRemap", json!({"layers": [nested]})).unwrap();
+    assert_eq!(app.ui.timeline.layer_reveal.get(&nested), Some(&vec!["timeRemap".to_string()]));
+    let rows = labels(&app);
+    let at = rows.iter().position(|r| r == "Inner").unwrap();
+    assert_eq!(rows[at + 1].trim(), "Time Remap", "{rows:?}");
+    // Through the selection (the Layer menu), turning it off again: nothing new is revealed.
+    app.session.execute("layer.select", json!({"layers": [nested]})).unwrap();
+    app.ui.timeline.layer_reveal.clear();
+    crate::menus::invoke(&mut app, &ctx, "layer.enableTimeRemap", json!({})).unwrap();
+    assert!(app.ui.timeline.layer_reveal.is_empty());
+}
+
+#[test]
+fn cti_snaps_to_the_nearest_candidate() {
+    assert_eq!(snap_time(&[0.0, 1.0, 2.0], 1.04, 0.1), 1.0);
+    assert_eq!(snap_time(&[0.0, 1.0, 2.0], 1.5, 0.1), 1.5);
+    assert_eq!(snap_time(&[1.0, 1.1], 1.06, 0.1), 1.1);
+    let app = app();
+    let comp = app.session.active_comp().unwrap().clone();
+    let c = snap_candidates(&comp, &build_rows(&app, &comp));
+    assert!(c.contains(&comp.duration.seconds()) && c.contains(&0.0));
+}
+
+/// Every string drawn by one frame of `draw`.
+fn drawn_text(mut draw: impl FnMut(&mut egui::Ui)) -> Vec<String> {
+    fn collect(shape: &egui::Shape, out: &mut Vec<String>) {
+        match shape {
+            egui::Shape::Text(t) => out.push(t.galley.text().to_string()),
+            egui::Shape::Vec(v) => v.iter().for_each(|s| collect(s, out)),
+            _ => {}
+        }
+    }
+    let ctx = egui::Context::default();
+    ctx.run_ui(Default::default(), |ui| draw(ui)).textures_delta.clear();
+    let mut frame = ctx.run_ui(Default::default(), |ui| draw(ui));
+    frame.textures_delta.clear();
+    let mut out = Vec::new();
+    frame.shapes.iter().for_each(|c| collect(&c.shape, &mut out));
+    out
+}
+
+/// #1308: the layer context menu draws its items in the interface language, from the menu
+/// bar's rows for the same commands (whose ellipsis is `...`), and its Effects submenu draws
+/// the categories the Effect menu does; the actions it records stay the same.
+#[test]
+fn the_layer_context_menu_draws_in_the_interface_language() {
+    let caps = LayerMenuCaps { vector: true, text: false, source: true };
+    let (mut auto, mut actions) = (crate::automation::Registry::default(), Vec::new());
+    crate::i18n::set_current("zh-hans");
+    let menu = drawn_text(|ui| layer_menu(ui, &[7], caps, (&mut auto, "t"), &mut actions));
+    let effects = drawn_text(|ui| effects_submenu(ui, &[7], &mut |_: &mut egui::Ui, _: &str, _: &str, _: serde_json::Value| {}));
+    crate::i18n::set_current("en");
+    let english = drawn_text(|ui| layer_menu(ui, &[7], caps, (&mut auto, "t"), &mut actions));
+    for label in ["新建", "图层设置...", "在项目中显示图层源", "从矢量图层创建形状", "预合成...", "重复", "拆分图层", "删除"]
+    {
+        assert!(menu.iter().any(|t| t == label), "{label} missing from {menu:?}");
+    }
+    assert!(!menu.iter().any(|t| t.is_ascii()), "English left in {menu:?}");
+    assert!(effects.iter().any(|t| t == "模糊和锐化"), "{effects:?}");
+    assert!(!effects.iter().any(|t| t == "Blur & Sharpen"), "{effects:?}");
+    for label in ["Layer Settings…", "Reveal Layer Source in Project", "Duplicate", "Delete"] {
+        assert!(english.iter().any(|t| t == label), "{label} missing from {english:?}");
+    }
+    assert!(actions.is_empty());
+}
+
+/// The property context menu draws its items in the interface language too: the commands the
+/// menu bar has from its rows, Reset, Edit Value… and Remove Expression from the panel catalog.
+/// The automation labels stay English.
+#[test]
+fn the_property_context_menu_draws_in_the_interface_language() {
+    let mut s = effectcraft_engine::Session::default();
+    s.execute("comp.new", json!({"name": "Main", "width": 64, "height": 64, "duration": 4})).unwrap();
+    let l = s.execute("layer.newSolid", json!({"name": "Plate", "color": "#406080"})).unwrap()["layer"].as_u64().unwrap();
+    let opacity = s.active_comp().unwrap().layer(LayerId(l)).unwrap().props.prop("transform/opacity").unwrap().uid;
+    s.execute("prop.setExpression", json!({"layer": l, "prop": opacity})).unwrap();
+    let comp = s.active_comp_id().unwrap();
+    let layer = s.active_comp().unwrap().layer(LayerId(l)).unwrap().clone();
+    let (position, opacity) = (layer.props.prop("transform/position").unwrap(), layer.props.prop("transform/opacity").unwrap());
+    let (mut auto, mut actions) = (crate::automation::Registry::default(), Vec::new());
+    let mut menu = |language| {
+        crate::i18n::set_current(language);
+        let mut drawn = drawn_text(|ui| prop_menu(ui, &mut auto, comp, &layer, position, &mut actions));
+        drawn.extend(drawn_text(|ui| prop_menu(ui, &mut auto, comp, &layer, opacity, &mut actions)));
+        drawn
+    };
+    let chinese = menu("zh-hans");
+    let english = menu("en");
+    for label in ["重置", "编辑值…", "单独尺寸", "添加表达式", "移除表达式", "向基本图形添加属性"] {
+        assert!(chinese.iter().any(|t| t == label), "{label} missing from {chinese:?}");
+    }
+    assert!(!chinese.iter().any(|t| t.is_ascii()), "English left in {chinese:?}");
+    for label in ["Reset", "Edit Value…", "Separate Dimensions", "Remove Expression", "Add Property to Essential Graphics"] {
+        assert!(english.iter().any(|t| t == label), "{label} missing from {english:?}");
+    }
+    assert!(auto.elements.iter().any(|e| e.label == "Remove Expression"), "the automation label stays English");
+    assert!(actions.is_empty());
+}
+
+/// UI fidelity (M13.5): compact After Effects-like rows and muted label-coloured bars.
+#[test]
+fn rows_and_bars_follow_after_effects_proportions() {
+    let t = crate::theme::Tokens::for_kind(crate::theme::ThemeKind::Dark);
+    assert_eq!(t.row_h, 19.0);
+    let red = t.label(effectcraft_engine::color::Label::Red);
+    let bar = bar_color(red, false);
+    // Muted: darker and less saturated than the label, still reddish.
+    assert!(bar.r() < red.r() && bar.r() > bar.g() + 30 && bar.g() >= red.g().min(0x3a) - 1);
+    let sel = bar_color(red, true);
+    assert!(sel.r() > bar.r());
+}
+
+#[test]
+fn disk_bar_range_covers_partial_frames() {
+    let clip = Rect::from_min_max(pos2(0.0, 0.0), pos2(2.0, 1.0));
+    let tm = TMap { x0: 0.0, start: 10.25, pps: 1.0 };
+    assert_eq!(disk_bar_range(&tm, clip, 1.0, 100), 10..13);
+
+    let exact = TMap { start: 10.0, ..tm };
+    assert_eq!(disk_bar_range(&exact, clip, 1.0, 100), 10..12);
+    let off_comp = TMap { start: 200.0, ..tm };
+    assert_eq!(disk_bar_range(&off_comp, clip, 1.0, 100), 100..100);
+    assert_eq!(disk_bar_range(&tm, clip, f64::NAN, 100), 0..0);
+    assert_eq!(disk_bar_range(&TMap { pps: 0.0, ..tm }, clip, 1.0, 100), 0..0);
+    assert_eq!(disk_bar_range(&TMap { start: f64::NAN, ..tm }, clip, 1.0, 100), 0..0);
+    assert_eq!(disk_bar_range(&tm, Rect::from_min_max(pos2(2.0, 0.0), pos2(2.0, 1.0)), 1.0, 100), 0..0);
+    let above_limit = TMap { start: 100_001.0, ..tm };
+    assert_eq!(disk_bar_range(&above_limit, clip, 1.0, i64::MAX), 100_000..100_000);
+}