diff --git a/crates/ui-egui/src/browser.rs b/crates/ui-egui/src/browser.rs
index 45e14b11..93107c07 100644
--- a/crates/ui-egui/src/browser.rs
+++ b/crates/ui-egui/src/browser.rs
@@ -281,6 +281,7 @@ fn draw_row(ui: &mut egui::Ui, id: egui::Id, row: &Row) -> RowResp {
         };
         ui.painter().add(egui::Shape::convex_polygon(pts, t.text_dim, Stroke::NONE));
         out.fold = ui.interact(ar.expand(3.0), id.with("fold"), Sense::click()).clicked();
+        crate::scenario::publish_handle(&format!("fold:{}", row.label), ar.center());
     }
     x += 14.0;
     // Eye.
@@ -322,6 +323,7 @@ fn draw_row(ui: &mut egui::Ui, id: egui::Id, row: &Row) -> RowResp {
         badge(ui.painter(), br, b, t.text_dim);
         bx += 15.0;
     }
+    crate::scenario::publish_handle(&format!("row:{}", row.label), r.center());
     out.resp = Some(resp.clone());
     out.clicked = resp.clicked();
     out.double = resp.double_clicked();
diff --git a/crates/ui-egui/src/control.rs b/crates/ui-egui/src/control.rs
index 8613bfff..d5233296 100644
--- a/crates/ui-egui/src/control.rs
+++ b/crates/ui-egui/src/control.rs
@@ -264,6 +264,12 @@ pub fn handle(app: &mut SolveApp, ctx: &egui::Context, req: &ControlRequest) ->
                 };
             }
             let Some(rect) = app.viewport.rect else { return err("no viewport") };
+            if let Some(c) = p.get("cube") {
+                // A point on the view cube, in cube units (faces at ±1).
+                let n = |i: usize| c.get(i).and_then(Value::as_f64).unwrap_or(0.0);
+                let q = crate::viewport::cube_point(app, rect, solvecraft_engine::geom::Vec3::new(n(0), n(1), n(2)));
+                return ok(json!([q.x, q.y]));
+            }
             let proj = crate::viewport::projection(app, rect);
             let num = |v: &Value, i: usize| v.get(i).and_then(Value::as_f64).unwrap_or(0.0);
             let world = if let Some(w) = p.get("world") {
diff --git a/crates/ui-egui/src/scenario.rs b/crates/ui-egui/src/scenario.rs
index 0b3c6851..f1128b1c 100644
--- a/crates/ui-egui/src/scenario.rs
+++ b/crates/ui-egui/src/scenario.rs
@@ -16,7 +16,10 @@
 //!   folder (Save pickers save there)
 //! - `{"shot": "name"}`: a screenshot when run in a window; headless, a render of the model
 //!   into `$SOLVECRAFT_SCENARIO_SHOTS` when that is set; `{"debug": 1}`
-//!   prints the UI state
+//!   prints the UI state (`"widgets"`: also every widget's text; `"handles"`: every published
+//!   handle, browser rows as `row:<label>` and their fold arrows as `fold:<label>`)
+//! - `{"camera": {"yaw": rad, "pitch": rad}}` puts the camera at an orbit; `{"view_anim": "top",
+//!   "max_deg": 10}` animates to a view and fails if any frame turns the view more than that
 //! - AT may also be `{"plane": "XY"}` (the middle of an origin plane's square), `{"axis": "Z"}`,
 //!   `{"dimension": "d1"}` or `{"handle": "arrow"}` (a manipulator handle: see [`publish_handle`])
 //! - `{"autosave": true}`: autosave into the scenario's recovery folder; `{"restart": "crash" |
@@ -40,26 +43,47 @@ thread_local! {
     /// Drag handles drawn this frame (name, screen point): manipulators publish theirs so
     /// scenarios (and the control channel's `ui.at {handle}`) can grab them.
     static HANDLES: RefCell<Vec<(String, egui::Pos2)>> = const { RefCell::new(Vec::new()) };
+    /// Painted parts with no widget of their own (the toolbar, the workspace switcher…): rects
+    /// and counts by name, for checks.
+    static RECTS: RefCell<Vec<(String, egui::Rect)>> = const { RefCell::new(Vec::new()) };
+    static COUNTS: RefCell<Vec<(String, f64)>> = const { RefCell::new(Vec::new()) };
 }
 
 /// A manipulator's handle drawn this frame at `at` (screen), by name: "arrow" (a dialog's value
 /// arrow), "triad_x"… Call it from the code that draws the handle, every frame it shows.
 pub fn publish_handle(name: &str, at: egui::Pos2) {
-    HANDLES.with(|h| {
-        let mut h = h.borrow_mut();
-        h.retain(|(n, _)| n != name);
-        h.push((name.to_string(), at));
-    });
+    // The latest wins (lookups search from the end), so publishing is cheap for browser rows.
+    HANDLES.with(|h| h.borrow_mut().push((name.to_string(), at)));
 }
 
 /// Where a handle was drawn last frame.
 pub fn handle_at(name: &str) -> Option<egui::Pos2> {
-    HANDLES.with(|h| h.borrow().iter().find(|(n, _)| n == name).map(|x| x.1))
+    HANDLES.with(|h| h.borrow().iter().rfind(|(n, _)| n == name).map(|x| x.1))
 }
 
-/// Forget last frame's handles (called as a frame starts).
+/// A painted part's rect this frame, by name ("toolbar", "workspace_switcher").
+pub fn publish_rect(name: &str, r: egui::Rect) {
+    RECTS.with(|h| h.borrow_mut().push((name.to_string(), r)));
+}
+
+pub fn rect_of(name: &str) -> Option<egui::Rect> {
+    RECTS.with(|h| h.borrow().iter().rfind(|(n, _)| n == name).map(|x| x.1))
+}
+
+/// A number about this frame's drawing, by name ("cube_highlights": the view cube's lit patches).
+pub fn publish_count(name: &str, v: f64) {
+    COUNTS.with(|h| h.borrow_mut().push((name.to_string(), v)));
+}
+
+pub fn count_of(name: &str) -> Option<f64> {
+    COUNTS.with(|h| h.borrow().iter().rfind(|(n, _)| n == name).map(|x| x.1))
+}
+
+/// Forget last frame's handles, rects and counts (called as a frame starts).
 pub fn clear_handles() {
     HANDLES.with(|h| h.borrow_mut().clear());
+    RECTS.with(|h| h.borrow_mut().clear());
+    COUNTS.with(|h| h.borrow_mut().clear());
 }
 
 /// A fresh folder for one scenario's files.
@@ -232,6 +256,36 @@ impl Harness {
         }
     }
 
+    /// Animate the view to `v` (as the view cube does), sampling the camera every frame: no
+    /// frame may turn the view (its right or back vector) by more than `max_deg`, the last
+    /// included, so the move ends without a jump.
+    fn view_anim(&mut self, v: &str, max_deg: f64) -> Result<(), String> {
+        let basis = |c: &solvecraft_engine::render::Camera| c.basis();
+        let mut prev = basis(&self.app.cam);
+        self.app.animate_view(v);
+        if self.app.cam_anim.is_none() {
+            return Err(format!("view_anim {v}: no animation started"));
+        }
+        let mut worst = (0.0f64, 0usize);
+        for i in 0..240 {
+            self.frame();
+            let now = basis(&self.app.cam);
+            let ang = |a: solvecraft_engine::geom::Vec3, b: solvecraft_engine::geom::Vec3| a.dot(b).clamp(-1.0, 1.0).acos().to_degrees();
+            let d = ang(prev.0, now.0).max(ang(prev.2, now.2));
+            if d > worst.0 {
+                worst = (d, i);
+            }
+            prev = now;
+            if self.app.cam_anim.is_none() {
+                if worst.0 > max_deg {
+                    return Err(format!("view_anim {v}: frame {} of {} turns the view {:.1}° (limit {max_deg}°)", worst.1 + 1, i + 1, worst.0));
+                }
+                return Ok(());
+            }
+        }
+        Err(format!("view_anim {v}: still animating after 240 frames"))
+    }
+
     /// Run one step.
     pub fn step(&mut self, s: &Value) -> Result<(), String> {
         let flag = |k: &str| s.get(k).and_then(Value::as_bool).unwrap_or(false);
@@ -279,6 +333,19 @@ impl Harness {
                     self.call("ui.render", json!({"path": path.to_string_lossy(), "width": 1000, "height": 700}));
                 }
                 return Ok(());
+            } else if let Some(c) = s.get("camera") {
+                // Put the camera at an orbit: {"yaw": rad, "pitch": rad}.
+                if let Some(y) = c.get("yaw").and_then(Value::as_f64) {
+                    self.app.cam.yaw = y;
+                }
+                if let Some(p) = c.get("pitch").and_then(Value::as_f64) {
+                    self.app.cam.pitch = p;
+                }
+                self.app.cam_anim = None;
+                self.frames(2);
+                return Ok(());
+            } else if let Some(v) = s.get("view_anim").and_then(Value::as_str) {
+                return self.view_anim(v, s.get("max_deg").and_then(Value::as_f64).unwrap_or(10.0));
             } else if s.get("autosave").is_some() {
                 self.start_autosave();
                 return Ok(());
@@ -288,6 +355,9 @@ impl Harness {
                 let mut old = std::mem::replace(&mut self.app, SolveApp::new(Session::default(), Services::default()));
                 if how == "close" {
                     crate::recovery_ui::close(&mut old);
+                    // The desktop saves its settings on close and loads them on the next start.
+                    let prefs = old.prefs();
+                    self.app.load_prefs(&prefs);
                 }
                 drop(old);
                 self.ctx = egui::Context::default();
@@ -330,6 +400,10 @@ impl Harness {
                         .collect();
                     eprintln!("widgets: {texts:?}");
                 }
+                if s["debug"] == json!("handles") {
+                    let names: Vec<String> = HANDLES.with(|h| h.borrow().iter().map(|(n, p)| format!("{n} @{:.0},{:.0}", p.x, p.y)).collect());
+                    eprintln!("handles: {names:?}");
+                }
                 return Ok(());
             } else if let Some(e) = s.get("until") {
                 // Background work (a sample being built, a preview): frames until the checks pass.
@@ -417,6 +491,71 @@ pub fn check(h: &mut Harness, e: &Value) -> Result<(), String> {
                     return Err(format!("errors: {bad:?}"));
                 }
             }
+            "shown_handles" | "hidden_handles" => {
+                // Published handles ("fold:Bodies", "row:Body1") drawn (or not) this frame.
+                for n in v.as_array().into_iter().flatten().filter_map(Value::as_str) {
+                    if handle_at(n).is_some() != (k == "shown_handles") {
+                        return Err(format!("{n}: want {}", if k == "shown_handles" { "shown" } else { "hidden" }));
+                    }
+                }
+            }
+            "handle_order" => {
+                // Published handles left to right in this order.
+                let xs: Vec<(String, Option<f32>)> =
+                    v.as_array().into_iter().flatten().filter_map(Value::as_str).map(|n| (n.to_string(), handle_at(n).map(|p| p.x))).collect();
+                if xs.iter().any(|x| x.1.is_none()) || xs.windows(2).any(|w| w[0].1 >= w[1].1) {
+                    return Err(format!("handle order: got {xs:?}"));
+                }
+            }
+            "count" => {
+                // {"count": {"name": n, "value": x}}: a published count.
+                let n = v["name"].as_str().unwrap_or_default();
+                let got = count_of(n);
+                if got != v["value"].as_f64() {
+                    return Err(format!("count {n}: got {got:?}, want {}", v["value"]));
+                }
+            }
+            "spans" => {
+                // {"spans": {"inner": a, "outer": b, "axis": "y", "tol": px}}: published rect a
+                // covers b's extent along the axis (within tol).
+                let (a, b) = (v["inner"].as_str().unwrap_or_default(), v["outer"].as_str().unwrap_or_default());
+                let (ra, rb) = (rect_of(a).ok_or(format!("no rect {a}"))?, rect_of(b).ok_or(format!("no rect {b}"))?);
+                let tol = v["tol"].as_f64().unwrap_or(4.0) as f32;
+                let (lo, hi) = if v["axis"] == "x" { (ra.x_range(), rb.x_range()) } else { (ra.y_range(), rb.y_range()) };
+                if (lo.min - hi.min).abs() > tol || (lo.max - hi.max).abs() > tol {
+                    return Err(format!("{a} {lo:?} does not span {b} {hi:?} (±{tol})"));
+                }
+            }
+            "dialog_docked" => {
+                // The command dialog: docked at the viewport's right, its width in [min, max].
+                let r = h.ctx.memory(|m| m.area_rect(egui::Id::new("sc_dialog"))).ok_or("no command dialog")?;
+                let vp = h.app.viewport.rect.unwrap_or(egui::Rect::NOTHING);
+                let (lo, hi) = (v["min"].as_f64().unwrap_or(260.0) as f32, v["max"].as_f64().unwrap_or(380.0) as f32);
+                if r.width() < lo - 0.5 || r.width() > hi + 0.5 {
+                    return Err(format!("dialog width {:.0}, want {lo}..{hi}", r.width()));
+                }
+                if (r.right() - vp.right()).abs() > 2.0 || r.top() < vp.top() || r.bottom() > vp.bottom() + 1.0 {
+                    return Err(format!("dialog {r:?} is not docked right inside the viewport {vp:?}"));
+                }
+            }
+            "windows_fit" => {
+                // Every open window lies on screen and is at most `max_width` wide.
+                let screen = h.ctx.content_rect();
+                let max_w = v["max_width"].as_f64().unwrap_or(720.0) as f32;
+                let rects: Vec<(egui::Id, egui::Rect)> = h.ctx.memory(|m| {
+                    m.areas()
+                        .visible_layer_ids()
+                        .into_iter()
+                        .filter(|l| l.order == egui::Order::Middle)
+                        .filter_map(|l| m.area_rect(l.id).map(|r| (l.id, r)))
+                        .collect()
+                });
+                for (id, r) in rects {
+                    if r.width() > max_w || !screen.expand(1.0).contains_rect(r) {
+                        return Err(format!("window {id:?} at {r:?} (width {:.0}) does not fit {screen:?} at ≤{max_w}", r.width()));
+                    }
+                }
+            }
             "dialog" => {
                 let d = &ui["dialog"];
                 let ok = match v {
diff --git a/crates/ui-egui/src/toolbar.rs b/crates/ui-egui/src/toolbar.rs
index 2dcd451b..c6dc31b5 100644
--- a/crates/ui-egui/src/toolbar.rs
+++ b/crates/ui-egui/src/toolbar.rs
@@ -243,6 +243,8 @@ pub fn toolbar(app: &mut SolveApp, ui: &mut egui::Ui) {
         let tabs_y = r.top() + 2.0;
         let ws = Rect::from_min_size(pos2(r.left() + 8.0, tabs_y + 26.0), vec2(96.0, 56.0));
         painter.rect(ws, 4.0, t.field, Stroke::new(1.0, t.border), egui::StrokeKind::Inside);
+        crate::scenario::publish_rect("toolbar", r);
+        crate::scenario::publish_rect("workspace_switcher", ws);
         painter.text(pos2(ws.center().x - 5.0, ws.top() + 14.0), Align2::CENTER_CENTER, "DESIGN", FontId::proportional(12.0), t.text);
         caret(&painter, pos2(ws.center().x + 26.0, ws.top() + 14.0), t.text);
         painter.text(pos2(ws.center().x, ws.top() + 34.0), Align2::CENTER_CENTER, "workspace", FontId::proportional(10.0), t.text_dim);
diff --git a/crates/ui-egui/src/viewport.rs b/crates/ui-egui/src/viewport.rs
index 9d82b6bd..119aac3d 100644
--- a/crates/ui-egui/src/viewport.rs
+++ b/crates/ui-egui/src/viewport.rs
@@ -1771,11 +1771,21 @@ fn cpu_render(app: &mut SolveApp, ctx: &egui::Context, painter: &egui::Painter,
     }
 }
 
+/// Where a point in view-cube units (faces at ±1) is drawn.
+pub(crate) fn cube_point(app: &SolveApp, rect: Rect, p: Vec3) -> Pos2 {
+    let (r, u, _) = app.cam.basis();
+    pos2(rect.right() - 80.0 + (p.dot(r) * CUBE_SCALE) as f32, rect.top() + 80.0 - (p.dot(u) * CUBE_SCALE) as f32)
+}
+
+/// Half a view cube face, in pixels.
+const CUBE_SCALE: f64 = 32.0;
+
 /// The view cube (top right): click a face for a standard view; the house resets.
 fn view_cube(app: &mut SolveApp, ui: &mut egui::Ui, rect: Rect) {
     let t = Tokens::get();
     let c = pos2(rect.right() - 80.0, rect.top() + 80.0);
-    let s = 32.0f64;
+    let s = CUBE_SCALE;
+    let mut lit = 0;
     let (r, u, b) = app.cam.basis();
     let to2 = |p: Vec3| -> (Pos2, f64) { (pos2(c.x + (p.dot(r) * s) as f32, c.y - (p.dot(u) * s) as f32), p.dot(b)) };
     let faces: [(Vec3, &str, StandardView); 6] = [
@@ -1820,6 +1830,7 @@ fn view_cube(app: &mut SolveApp, ui: &mut egui::Ui, rect: Rect) {
             let ((a0, a1), (b0, b1)) = (lo(zi), lo(zj));
             let zp: Vec<Pos2> = [(a0, b0), (a1, b0), (a1, b1), (a0, b1)].iter().map(|(x, y)| to2(n + e1 * *x + e2 * *y).0).collect();
             painter.add(Shape::convex_polygon(zp, t.accent_soft, Stroke::NONE));
+            lit += 1;
         }
         let center = to2(n).0;
         if n.dot(b) > 0.35 {
@@ -1831,6 +1842,7 @@ fn view_cube(app: &mut SolveApp, ui: &mut egui::Ui, rect: Rect) {
             clicked = Some(n + e1 * zi as f64 + e2 * zj as f64);
         }
     }
+    crate::scenario::publish_count("cube_highlights", f64::from(lit));
     // Axis triad at the cube's corner.
     let o = Vec3::new(-1.0, -1.0, -1.0);
     for (d, col) in [(Vec3::X, colors::AXIS_X), (Vec3::Y, colors::AXIS_Y), (Vec3::Z, colors::AXIS_Z)] {
diff --git a/crates/ui-egui/tests/scenarios.rs b/crates/ui-egui/tests/scenarios.rs
index 87ea05f6..fb4b84d6 100644
--- a/crates/ui-egui/tests/scenarios.rs
+++ b/crates/ui-egui/tests/scenarios.rs
@@ -72,4 +72,22 @@ macro_rules! pending {
 
 pending!(
     s31_sketch_on_face_projects: "user bug: a sketch on a face projects its loops as reference (solvecraft-sketch)",
+    s37_browser_chevrons: "every chevron works; the browser has no Joints folder (solvecraft-shell)",
+    s38_view_anim_no_jump: "the last frame of an animation to Top turns the view 22.5 degrees (solvecraft-ui)",
+    s39_view_cube_hover: "view cube edge and corner hover light 1 patch, Fusion lights 2 and 3 (solvecraft-ui)",
+    s40_toolbar_customize_persists: "toolbar Pin/Remove/reorder (toolbar:<id> handles, ui.menu toolbar_command) and a full-height workspace switcher (solvecraft-shell)",
 );
+
+/// A scenario file named by `SOLVECRAFT_SCENARIO_FILE` (for trying one out):
+/// `SOLVECRAFT_SCENARIO_FILE=x.json cargo test --test scenarios adhoc -- --ignored --nocapture`.
+#[test]
+#[ignore]
+fn adhoc() {
+    let Ok(path) = std::env::var("SOLVECRAFT_SCENARIO_FILE") else { return };
+    let text = std::fs::read_to_string(&path).unwrap_or_else(|e| panic!("{path}: {e}"));
+    let steps: serde_json::Value = serde_json::from_str(&text).unwrap_or_else(|e| panic!("{path}: {e}"));
+    let mut h = Harness::new();
+    if let Err(e) = h.run(&steps) {
+        panic!("{path}: {e}");
+    }
+}
diff --git a/crates/ui-egui/tests/scenarios/s37_browser_chevrons.json b/crates/ui-egui/tests/scenarios/s37_browser_chevrons.json
new file mode 100644
index 00000000..33a13cd8
--- /dev/null
+++ b/crates/ui-egui/tests/scenarios/s37_browser_chevrons.json
@@ -0,0 +1,523 @@
+[
+ {
+  "note": "Browser chevrons expand and collapse every kind of node (folders, components, groups, the origin, named views, document settings). Model: two components with a body each, a joint, a sketch, an offset plane, a named view."
+ },
+ {
+  "start": "FusionCreateNewComponentCommand"
+ },
+ {
+  "key": "Enter"
+ },
+ {
+  "start": "SketchCreate"
+ },
+ {
+  "click": {
+   "plane": "XY"
+  }
+ },
+ {
+  "start": "ShapeRectangleTwoPoint"
+ },
+ {
+  "click": {
+   "sketch": [
+    0,
+    0
+   ]
+  }
+ },
+ {
+  "click": {
+   "sketch": [
+    20,
+    20
+   ]
+  }
+ },
+ {
+  "key": "Escape"
+ },
+ {
+  "start": "SketchStop"
+ },
+ {
+  "call": "ui.view",
+  "params": {
+   "view": "iso"
+  }
+ },
+ {
+  "start": "Extrude"
+ },
+ {
+  "text": "10"
+ },
+ {
+  "key": "Enter"
+ },
+ {
+  "call": "ui.menu",
+  "params": {
+   "x": 100,
+   "y": 170,
+   "target": {
+    "type": "component",
+    "id": 0
+   }
+  }
+ },
+ {
+  "call": "ui.menuPick",
+  "params": {
+   "item": "Activate"
+  }
+ },
+ {
+  "start": "FusionCreateNewComponentCommand"
+ },
+ {
+  "key": "Enter"
+ },
+ {
+  "start": "SketchCreate"
+ },
+ {
+  "click": {
+   "plane": "XZ"
+  }
+ },
+ {
+  "start": "ShapeRectangleTwoPoint"
+ },
+ {
+  "click": {
+   "sketch": [
+    30,
+    0
+   ]
+  }
+ },
+ {
+  "click": {
+   "sketch": [
+    50,
+    10
+   ]
+  }
+ },
+ {
+  "key": "Escape"
+ },
+ {
+  "start": "SketchStop"
+ },
+ {
+  "call": "ui.view",
+  "params": {
+   "view": "iso"
+  }
+ },
+ {
+  "start": "Extrude"
+ },
+ {
+  "click": {
+   "world": [
+    40,
+    0,
+    5
+   ]
+  }
+ },
+ {
+  "text": "20"
+ },
+ {
+  "key": "Enter"
+ },
+ {
+  "expect": {
+   "bodies": 2,
+   "errors": 0
+  }
+ },
+ {
+  "start": "JointAssembleCmdNew"
+ },
+ {
+  "click": {
+   "world": [
+    10,
+    10,
+    10
+   ]
+  }
+ },
+ {
+  "click": {
+   "world": [
+    40,
+    0,
+    5
+   ]
+  }
+ },
+ {
+  "widget": "Rigid"
+ },
+ {
+  "widget": "Revolute"
+ },
+ {
+  "widget": "OK"
+ },
+ {
+  "call": "engine.execute",
+  "params": {
+   "command": "ConstructionPlaneOffsetFromPlaneCommand",
+   "params": {
+    "base": "XY",
+    "offset": 30
+   }
+  }
+ },
+ {
+  "key": "Escape"
+ },
+ {
+  "call": "ui.menu",
+  "params": {
+   "x": 100,
+   "y": 300,
+   "target": {
+    "type": "named_views"
+   }
+  }
+ },
+ {
+  "call": "ui.menuPick",
+  "params": {
+   "item": "New Named View"
+  }
+ },
+ {
+  "note": "Each kind of node: its chevron hides its children, and shows them again."
+ },
+ {
+  "click": {
+   "handle": "fold:Document Settings"
+  }
+ },
+ {
+  "expect": {
+   "shown_handles": [
+    "row:Units: mm"
+   ]
+  }
+ },
+ {
+  "click": {
+   "handle": "fold:Document Settings"
+  }
+ },
+ {
+  "expect": {
+   "hidden_handles": [
+    "row:Units: mm"
+   ]
+  }
+ },
+ {
+  "click": {
+   "handle": "fold:Document Settings"
+  }
+ },
+ {
+  "expect": {
+   "shown_handles": [
+    "row:Units: mm"
+   ]
+  }
+ },
+ {
+  "expect": {
+   "shown_handles": [
+    "row:Named View1"
+   ]
+  }
+ },
+ {
+  "click": {
+   "handle": "fold:Named Views"
+  }
+ },
+ {
+  "expect": {
+   "hidden_handles": [
+    "row:Named View1"
+   ]
+  }
+ },
+ {
+  "click": {
+   "handle": "fold:Named Views"
+  }
+ },
+ {
+  "expect": {
+   "shown_handles": [
+    "row:Named View1"
+   ]
+  }
+ },
+ {
+  "click": {
+   "handle": "fold:Origin"
+  }
+ },
+ {
+  "expect": {
+   "shown_handles": [
+    "row:XY"
+   ]
+  }
+ },
+ {
+  "click": {
+   "handle": "fold:Origin"
+  }
+ },
+ {
+  "expect": {
+   "hidden_handles": [
+    "row:XY"
+   ]
+  }
+ },
+ {
+  "click": {
+   "handle": "fold:Origin"
+  }
+ },
+ {
+  "expect": {
+   "shown_handles": [
+    "row:XY"
+   ]
+  }
+ },
+ {
+  "expect": {
+   "shown_handles": [
+    "row:Body2"
+   ]
+  }
+ },
+ {
+  "click": {
+   "handle": "fold:Bodies"
+  }
+ },
+ {
+  "expect": {
+   "hidden_handles": [
+    "row:Body2"
+   ]
+  }
+ },
+ {
+  "click": {
+   "handle": "fold:Bodies"
+  }
+ },
+ {
+  "expect": {
+   "shown_handles": [
+    "row:Body2"
+   ]
+  }
+ },
+ {
+  "expect": {
+   "shown_handles": [
+    "row:Sketch2"
+   ]
+  }
+ },
+ {
+  "click": {
+   "handle": "fold:Sketches"
+  }
+ },
+ {
+  "expect": {
+   "hidden_handles": [
+    "row:Sketch2"
+   ]
+  }
+ },
+ {
+  "click": {
+   "handle": "fold:Sketches"
+  }
+ },
+ {
+  "expect": {
+   "shown_handles": [
+    "row:Sketch2"
+   ]
+  }
+ },
+ {
+  "expect": {
+   "shown_handles": [
+    "row:Plane1"
+   ]
+  }
+ },
+ {
+  "click": {
+   "handle": "fold:Construction"
+  }
+ },
+ {
+  "expect": {
+   "hidden_handles": [
+    "row:Plane1"
+   ]
+  }
+ },
+ {
+  "click": {
+   "handle": "fold:Construction"
+  }
+ },
+ {
+  "expect": {
+   "shown_handles": [
+    "row:Plane1"
+   ]
+  }
+ },
+ {
+  "expect": {
+   "shown_handles": [
+    "row:Sketch2"
+   ]
+  }
+ },
+ {
+  "click": {
+   "handle": "fold:Component2:1"
+  }
+ },
+ {
+  "expect": {
+   "hidden_handles": [
+    "row:Sketch2"
+   ]
+  }
+ },
+ {
+  "click": {
+   "handle": "fold:Component2:1"
+  }
+ },
+ {
+  "expect": {
+   "shown_handles": [
+    "row:Sketch2"
+   ]
+  }
+ },
+ {
+  "expect": {
+   "shown_handles": [
+    "row:Sketch1"
+   ]
+  }
+ },
+ {
+  "click": {
+   "handle": "fold:Component1:1"
+  }
+ },
+ {
+  "expect": {
+   "hidden_handles": [
+    "row:Sketch1"
+   ]
+  }
+ },
+ {
+  "click": {
+   "handle": "fold:Component1:1"
+  }
+ },
+ {
+  "expect": {
+   "shown_handles": [
+    "row:Sketch1"
+   ]
+  }
+ },
+ {
+  "expect": {
+   "shown_handles": [
+    "row:Origin"
+   ]
+  }
+ },
+ {
+  "click": {
+   "handle": "fold:Untitled"
+  }
+ },
+ {
+  "expect": {
+   "hidden_handles": [
+    "row:Origin"
+   ]
+  }
+ },
+ {
+  "click": {
+   "handle": "fold:Untitled"
+  }
+ },
+ {
+  "expect": {
+   "shown_handles": [
+    "row:Origin"
+   ]
+  }
+ },
+ {
+  "note": "The joints folder lists the joint (Fusion's Joints folder in the root component)."
+ },
+ {
+  "expect": {
+   "shown_handles": [
+    "fold:Joints"
+   ]
+  }
+ },
+ {
+  "click": {
+   "handle": "fold:Joints"
+  }
+ },
+ {
+  "click": {
+   "handle": "fold:Joints"
+  }
+ },
+ {
+  "expect": {
+   "shown_handles": [
+    "fold:Joints"
+   ]
+  }
+ }
+]
\ No newline at end of file
diff --git a/crates/ui-egui/tests/scenarios/s38_view_anim_no_jump.json b/crates/ui-egui/tests/scenarios/s38_view_anim_no_jump.json
new file mode 100644
index 00000000..996fd8ce
--- /dev/null
+++ b/crates/ui-egui/tests/scenarios/s38_view_anim_no_jump.json
@@ -0,0 +1,20 @@
+[
+ {"note": "Animating to Top or Bottom from iso, front or any orbit turns the view smoothly to the end: no frame (the last included) turns it more than 10 degrees."},
+ {"start": "PrimitiveBox"},
+ {"key": "Escape"},
+ {"view_anim": "top"},
+ {"view_anim": "home"},
+ {"view_anim": "bottom"},
+ {"call": "ui.view", "params": {"view": "front"}},
+ {"view_anim": "top"},
+ {"call": "ui.view", "params": {"view": "front"}},
+ {"view_anim": "bottom"},
+ {"camera": {"yaw": 2.3, "pitch": 0.35}},
+ {"view_anim": "top"},
+ {"camera": {"yaw": -1.1, "pitch": -0.4}},
+ {"view_anim": "top"},
+ {"camera": {"yaw": 2.3, "pitch": 0.35}},
+ {"view_anim": "bottom"},
+ {"camera": {"yaw": 0.4, "pitch": 1.2}},
+ {"view_anim": "front"}
+]
diff --git a/crates/ui-egui/tests/scenarios/s39_view_cube_hover.json b/crates/ui-egui/tests/scenarios/s39_view_cube_hover.json
new file mode 100644
index 00000000..1e0d1689
--- /dev/null
+++ b/crates/ui-egui/tests/scenarios/s39_view_cube_hover.json
@@ -0,0 +1,16 @@
+[
+ {"note": "View cube hover from the home view: a face lights one patch, an edge the 2 patches on its faces, a corner the 3 around it (Fusion)."},
+ {"call": "ui.view", "params": {"view": "home"}},
+ {"move": {"cube": [0, 0, 1]}},
+ {"expect": {"count": {"name": "cube_highlights", "value": 1}}},
+ {"move": {"cube": [0, -0.9, 1]}},
+ {"expect": {"count": {"name": "cube_highlights", "value": 2}}},
+ {"move": {"cube": [1, -0.9, 0]}},
+ {"expect": {"count": {"name": "cube_highlights", "value": 2}}},
+ {"move": {"cube": [0.9, -0.9, 1]}},
+ {"expect": {"count": {"name": "cube_highlights", "value": 3}}},
+ {"move": {"cube": [0.9, -1, 0.9]}},
+ {"expect": {"count": {"name": "cube_highlights", "value": 3}}},
+ {"move": [800, 500]},
+ {"expect": {"count": {"name": "cube_highlights", "value": 0}}}
+]
diff --git a/crates/ui-egui/tests/scenarios/s40_toolbar_customize_persists.json b/crates/ui-egui/tests/scenarios/s40_toolbar_customize_persists.json
new file mode 100644
index 00000000..6a4d5ccc
--- /dev/null
+++ b/crates/ui-egui/tests/scenarios/s40_toolbar_customize_persists.json
@@ -0,0 +1,17 @@
+[
+ {"note": "Toolbar customizing like Fusion survives a restart: Pin to Toolbar, Remove from Toolbar, drag to reorder. Toolbar buttons publish handles `toolbar:<command id>`. The workspace switcher spans the toolbar's height."},
+ {"expect": {"spans": {"inner": "workspace_switcher", "outer": "toolbar", "axis": "y", "tol": 6}}},
+ {"expect": {"shown_handles": ["toolbar:Extrude", "toolbar:Revolve"], "hidden_handles": ["toolbar:FusionShellBodyCommand"]}},
+ {"call": "ui.menu", "params": {"x": 400, "y": 80, "target": {"type": "toolbar_command", "id": "FusionShellBodyCommand"}}},
+ {"call": "ui.menuPick", "params": {"item": "Pin to Toolbar"}},
+ {"expect": {"shown_handles": ["toolbar:FusionShellBodyCommand"]}},
+ {"call": "ui.menu", "params": {"x": 400, "y": 80, "target": {"type": "toolbar_command", "id": "Revolve"}}},
+ {"call": "ui.menuPick", "params": {"item": "Remove from Toolbar"}},
+ {"expect": {"hidden_handles": ["toolbar:Revolve"]}},
+ {"drag": [{"handle": "toolbar:FusionShellBodyCommand"}, {"handle": "toolbar:Extrude"}], "steps": 12},
+ {"expect": {"handle_order": ["toolbar:FusionShellBodyCommand", "toolbar:Extrude"]}},
+ {"restart": "close"},
+ {"expect": {"shown_handles": ["toolbar:FusionShellBodyCommand"], "hidden_handles": ["toolbar:Revolve"]}},
+ {"expect": {"handle_order": ["toolbar:FusionShellBodyCommand", "toolbar:Extrude"]}},
+ {"expect": {"spans": {"inner": "workspace_switcher", "outer": "toolbar", "axis": "y", "tol": 6}}}
+]
diff --git a/crates/ui-egui/tests/ui_layout.rs b/crates/ui-egui/tests/ui_layout.rs
new file mode 100644
index 00000000..f5e50c2e
--- /dev/null
+++ b/crates/ui-egui/tests/ui_layout.rs
@@ -0,0 +1,67 @@
+//! Layout checks over every toolbar command, headless (see `solvecraft_ui_egui::scenario`):
+//! each command's dialog opens docked at the viewport's right within its width limits, and
+//! every window it opens fits on screen.
+
+use serde_json::{Value, json};
+use solvecraft_ui_egui::scenario::{Harness, check};
+
+/// A box body (its sketch finished) to give feature dialogs something to work on.
+fn harness() -> Harness {
+    let mut h = Harness::new();
+    for (id, p) in [
+        ("SketchCreate", json!({"plane": "XY"})),
+        ("ShapeRectangleTwoPoint", json!({"p0": [0, 0], "p1": [40, 30]})),
+        ("SketchStop", json!({})),
+        ("Extrude", json!({"distance": 10})),
+    ] {
+        h.call("engine.execute", json!({"command": id, "params": p}));
+    }
+    h.frames(3);
+    h
+}
+
+#[test]
+#[ignore = "pending: the exploded view dialog opens 635 px wide (solvecraft-ui)"]
+fn every_dialog_opens_docked_within_its_width_limits() {
+    let mut bad = Vec::new();
+    let mut seen = 0;
+    for spec in solvecraft_engine::command_specs() {
+        if spec.tab.is_empty() || spec.tab == "SKETCH" {
+            continue;
+        }
+        let mut h = harness();
+        h.call("ui.start", json!({"command": spec.id}));
+        h.frames(4);
+        if h.app.dialog.is_some() {
+            seen += 1;
+            // Command dialogs are 260–380 px (plus their 1 px border), the few with tables
+            // (motion study, configurations) 480–560.
+            let w = h.ctx.memory(|m| m.area_rect(egui::Id::new("sc_dialog"))).map_or(0.0, |r| r.width());
+            let limits = if w > 400.0 { json!({"min": 480, "max": 562}) } else { json!({"min": 260, "max": 382}) };
+            if let Err(e) = check(&mut h, &json!({ "dialog_docked": limits })) {
+                bad.push(format!("{}: {e}", spec.id));
+            }
+        }
+        if let Err(e) = check(&mut h, &json!({"windows_fit": {"max_width": 900}})) {
+            bad.push(format!("{}: {e}", spec.id));
+        }
+    }
+    assert!(seen > 20, "only {seen} commands opened a dialog");
+    assert!(bad.is_empty(), "{} problems:\n{}", bad.len(), bad.join("\n"));
+}
+
+/// Windows that are not command dialogs: each fits on screen.
+#[test]
+fn other_windows_fit_on_screen() {
+    let mut bad = Vec::new();
+    let opens: [(&str, Value); 3] = [("ui.help", json!({"item": "about"})), ("ui.key", json!({"key": "S"})), ("ui.prefs", json!({"open": true}))];
+    for (m, p) in opens {
+        let mut h = harness();
+        h.call(m, p.clone());
+        h.frames(4);
+        if let Err(e) = check(&mut h, &json!({"windows_fit": {"max_width": 900}})) {
+            bad.push(format!("{m} {p}: {e}"));
+        }
+    }
+    assert!(bad.is_empty(), "{}", bad.join("\n"));
+}