Fix mobile chip-strip overlap, reveal-replay stagger, scroll-linked text-fill

Three clone-fidelity fixes from manual review of the acceptance screenshots.

Fix 1 — mobile nav chip-strip overlap (generate/css.ts). A horizontally
scrollable flex strip (overflow-x:auto flex <ul>) of nowrap chips collapsed
because the base viewport reported min-width:0px on the chips (a mobile-only
strip that is 0-wide at desktop), so the generator emitted `min-w-0`, letting
the chips shrink below their content instead of overflowing — the nowrap text
then collided. Suppress `min-w-0` for a nowrap flex item whose flex parent
scrolls horizontally; scoped away from legitimate min-w-0 truncation (whose
parent does not scroll-x). Verified on a fresh ooni.com clone: 0 chip overlaps
at 375, scrollWidth 776 > clientWidth 375.

Fix 2 — reveal-replay stagger leaves tiles unpainted (generate/motion.ts).
DittoMotion re-hid each revealed element and replayed its entrance on
scroll-into-view preserving the captured delay/duration, so a fast scroll /
full-page screenshot caught most grid tiles mid-entrance. Cap the replayed
delay (<=300ms) and duration (<=600ms), settle each tile per-element a bounded
time after it enters view, and make the global failsafe settle (not re-animate)
so nothing stays hidden. Validator settle path (__dittoMotionStop) unchanged.
Verified: cropin cotton renders 12/12 crop tiles in a normal full-page pass;
motion gate reveals 24/24.

Fix 3 — scroll-linked text-fill frozen at end state (capture/stabilize.ts,
capture/capture.ts, generate/css.ts). A view-timeline text-fill
(animation-duration resolves to `auto`) was baked filled: the clone has no
scroll timeline, so emitting the animation made it jump to its end keyframe via
fill-mode:both. Capture-side, cancel scroll/view-timeline animations before each
snapshot so the DOM records the at-rest state; generation-side, suppress the
animation-* props when animation-duration is `auto` (we render the at-rest
state, never replay a scroll-linked animation). Teach the motion gate to exclude
these from the static-CSS expectation so the gate stays honest. Verified on a
fresh ooni clone: the "world's no.1 pizza ovens" em is white/gray (rgb 240,240,
240), not filled yellow, at rest; motion gate still passes.

Tests: +7 fixtures (css scroll-strip + scroll-timeline, reveal-replay caps,
motion-gate scroll-timeline exclusion); 123/123 compiler tests green, full test
suite green, typecheck clean. No gate regression on the fresh ooni run vs the
20260704-024247 baseline (all gate pass/fail unchanged; perceptual within
0.0004; motion restored to pass).

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

compiler/src/capture/capture.ts

@@ -5,7 +5,7 @@ import { tagElements, captureInteractions, type InteractionCapture } from "./int
 import { captureMotion, probeReveals, type MotionCapture } from "./motion.js";
 import {
   promoteLazyMedia, settleCarousels, settleScrollReveals, neutralizePreReveal,
-  forceRevealForShot, restoreRevealForShot,
+  forceRevealForShot, restoreRevealForShot, neutralizeScrollTimelineAnimations,
 } from "./stabilize.js";
 import {
   enumerateFramesInPage, planForFrameUrl, graftFrameIntoSnapshot, frameHasRenderableContent,
@@ -965,6 +965,14 @@ export async function captureSite(opts: {
         await page.waitForTimeout(80);
       }
 
+      // Scroll-linked animations (animation-timeline: scroll()/view()) are held at their
+      // end keyframe by `fill-mode:both` after the dwell-scroll pass, even with scroll reset
+      // to 0 — so the walk would bake the frozen END state (e.g. a text-fill stuck at 100%).
+      // Cancel them here so the snapshot records the genuine AT-REST (unscrolled, 0%) values.
+      // Time-based reveals use the default document timeline and are untouched.
+      const scrollAnimsCanceled = await neutralizeScrollTimelineAnimations(page);
+      if (scrollAnimsCanceled) log({ event: "scroll_timeline_anims_canceled", viewport: vw, count: scrollAnimsCanceled });
+
       // Bound the in-page DOM walk: page.evaluate has no default timeout, so a
       // pathologically large/animated DOM (e.g. asana.com) could hang forever.
       const snapshot: PageSnapshot = await Promise.race([

compiler/src/capture/stabilize.ts

@@ -243,6 +243,67 @@ export async function neutralizePreReveal(page: Page): Promise<number> {
   }
 }
 
+/** Cancel scroll/view-timeline-driven CSS animations so the snapshot records the AT-REST
+ *  (unscrolled) computed style rather than a frozen mid/end-timeline value.
+ *
+ *  A scroll-linked text-fill (e.g. `animation-timeline: view(); animation-fill-mode: both`)
+ *  progresses with scroll position, not time. The dwell-scroll pass runs the page to the
+ *  bottom, and `fill-mode: both` HOLDS the animation's end keyframe even after we restore
+ *  scroll to 0 — because the element's view-timeline range has already been exited. The DOM
+ *  walk then reads the FROZEN end value (e.g. `background-position: 100%`, fully filled),
+ *  baking the end state into the clone when the live at-rest state is the start (0%).
+ *
+ *  Fix: before the snapshot, cancel every running CSS animation whose timeline is NOT the
+ *  default (document) timeline — i.e. a ScrollTimeline / ViewTimeline, or (fallback) an
+ *  animation whose resolved effect duration is not finite. Canceling drops the animation's
+ *  fill so getComputedStyle reports the underlying (unanimated) property values.
+ *
+ *  Scoped to scroll/view timelines only: time-based entrance animations (reveals) use the
+ *  default document timeline with a finite duration and are left untouched. */
+export function neutralizeScrollTimelineAnimationsInPage(): number {
+  let n = 0;
+  try {
+    const docTimeline = (document as unknown as { timeline?: unknown }).timeline;
+    const anims = (document as unknown as { getAnimations?: () => Animation[] }).getAnimations?.() ?? [];
+    for (const a of anims) {
+      try {
+        const tl = a.timeline as unknown;
+        // Default (document) timeline → time-based; leave it. Anything else (scroll/view
+        // timeline) or a null timeline with a non-finite effect duration → scroll-linked.
+        const isDefaultTimeline = tl === docTimeline;
+        const ctorName: string = (tl ? (tl as { constructor?: { name?: string } }).constructor?.name : "") || "";
+        const isScrollLinked =
+          !isDefaultTimeline && /Scroll|View/.test(ctorName);
+        // Fallback: resolved effect duration is not a finite number (scroll-timeline
+        // animations report `auto`/non-finite computed duration, e.g. `animation-duration:auto`).
+        let nonFiniteDuration = false;
+        try {
+          const timing = (a.effect as unknown as { getComputedTiming?: () => { duration?: number | string } })?.getComputedTiming?.();
+          const dur = timing?.duration;
+          nonFiniteDuration = typeof dur === "number" ? !isFinite(dur) : dur === "auto";
+        } catch { /* ignore */ }
+        if (isScrollLinked || (!isDefaultTimeline && nonFiniteDuration)) {
+          a.cancel();
+          n++;
+        }
+      } catch { /* per-animation errors are non-fatal */ }
+    }
+  } catch { /* getAnimations unsupported — no-op */ }
+  return n;
+}
+
+/** Node-side wrapper: bounded + never fatal. */
+export async function neutralizeScrollTimelineAnimations(page: Page): Promise<number> {
+  try {
+    return await Promise.race([
+      page.evaluate(neutralizeScrollTimelineAnimationsInPage),
+      new Promise<number>((res) => setTimeout(() => res(0), 5000)),
+    ]);
+  } catch {
+    return 0;
+  }
+}
+
 // ---- Carousel settling (runs in the page) ----
 
 export type CarouselSettleResult = { roots: number; normalized: number; neutralizedAnims: number };

compiler/src/generate/css.ts

@@ -2229,6 +2229,18 @@ function declsForViewport(
   const ov = cs.overflowY || cs.overflow || "visible";
   const parentDisp = parentComputed?.display || "";
   const isFlexGridItem = /flex|grid/.test(parentDisp);
+  // A chip in a horizontally-scrollable flex strip (an overflow-x:auto/scroll flex parent) relies on
+  // the CSS default `min-width:auto` to stay at its content width so the strip scrolls. The base
+  // viewport can report `min-width:0px` on such an item (e.g. a mobile-only strip collapsed to 0 at
+  // desktop), which would emit `min-w-0` and let the item shrink below its content — collapsing the
+  // strip and colliding its nowrap text. Suppress `min-w-0` for a nowrap flex item whose flex parent
+  // scrolls horizontally. This is scoped away from legitimate `min-w-0` truncation (overflow:hidden +
+  // ellipsis on the item itself, whose parent does NOT scroll-x), so it is safe.
+  const parentOverflowX = parentComputed ? (parentComputed.overflowX || parentComputed.overflow || "visible") : "visible";
+  const inScrollXFlexStrip =
+    /flex/.test(parentDisp) &&
+    /^(auto|scroll)$/.test(parentOverflowX) &&
+    (cs.whiteSpace || "normal") === "nowrap";
   const isLeaf = !hasElementChild(node);
   const hasText = node.children.some((c) => isTextChild(c) && c.text.trim() !== "");
   const isTextLeaf = isLeaf && hasText && !REPLACED.has(tag) && tag !== "canvas" && !tag.includes("-");
@@ -2417,7 +2429,16 @@ function declsForViewport(
   }
 
   const hasTransform = cs.transform && cs.transform !== "none";
-  const hasAnimation = cs.animationName && cs.animationName !== "none";
+  // A scroll/view-timeline-driven animation reports its resolved `animation-duration` as
+  // `auto` (the duration is derived from the timeline range, not a time). The clone has no
+  // scroll timeline, so emitting such an animation makes it jump straight to its END keyframe
+  // (`fill-mode:both` + a 0s time-based duration), freezing the element at the fully-progressed
+  // state (e.g. a scroll-linked text-fill stuck 100% filled). We do NOT replay scroll-linked
+  // animations; the goal is the correct AT-REST render. So suppress the animation-* props for
+  // an animation whose duration is `auto`, and let the captured static properties (now recorded
+  // at-rest, scroll reset + timeline animations canceled before the snapshot) stand.
+  const isScrollTimelineAnim = (cs.animationDuration || "").split(",").some((d) => d.trim() === "auto");
+  const hasAnimation = cs.animationName && cs.animationName !== "none" && !isScrollTimelineAnim;
 
   for (const { prop, def } of GENERIC) {
     const value = cs[prop];
@@ -2453,7 +2474,7 @@ function declsForViewport(
       if (!/^(ul|ol|li|menu)$/.test(tag)) continue;
       // list reset is none; emit whatever the source uses (incl. none).
     } else if (prop === "minWidth") {
-      if (value === "auto" || (value === "0px" && !isFlexGridItem)) continue;
+      if (value === "auto" || (value === "0px" && !isFlexGridItem) || (value === "0px" && inScrollXFlexStrip)) continue;
     } else if (def === "__never__") {
       // always emit (display/color/fontFamily/fontSize handled below for inherit)
     } else if (isDefault(def, value)) {

compiler/src/generate/motion.ts

@@ -116,6 +116,36 @@ export type MotionSpec = { waapi: RTWaapi[]; rotators: RTRotator[]; reveals: RTR
 
 const byCid = (cid: string): HTMLElement | null => document.querySelector('[data-cid="' + cid + '"]');
 
+// Reveal-replay pacing caps. On the live site an entrance stagger plays ONCE, on first load,
+// while the whole group is already in view. Our replay re-hides each element and replays its
+// entrance on scroll-into-view, preserving the captured per-element delay AND duration. A grid
+// of tiles then either staggers over a long window (captured delays) or each tile plays a long
+// (e.g. 1.25s) entrance as it scrolls in — so a fast scroll / full-page screenshot catches most
+// tiles mid-entrance, unpainted. Cap the replayed delay AND duration so each tile paints promptly
+// after it enters the viewport, keeping relative order. (The validator settles via
+// __dittoMotionStop and is unaffected — this only bounds the live, un-stopped replay.)
+const REVEAL_MAX_DELAY_MS = 300;
+const REVEAL_MAX_DURATION_MS = 600;
+const parseTimeMs = (raw: string | undefined): number => {
+  if (!raw) return 0;
+  const first = String(raw).split(",")[0]!.trim();
+  const m = /^(-?[0-9.]+)(ms|s)?$/.exec(first);
+  if (!m) return 0;
+  let ms = parseFloat(m[1]!);
+  if (m[2] !== "ms") ms *= 1000;
+  return isFinite(ms) ? ms : 0;
+};
+const clampDelay = (raw: string | undefined): string => {
+  const ms = parseTimeMs(raw);
+  if (ms <= 0) return "0s";
+  return Math.min(ms, REVEAL_MAX_DELAY_MS) + "ms";
+};
+const clampDuration = (raw: string | undefined): string => {
+  const ms = parseTimeMs(raw);
+  if (ms <= 0) return raw && String(raw).trim() ? String(raw) : "1s";
+  return Math.min(ms, REVEAL_MAX_DURATION_MS) + "ms";
+};
+
 /** Replays captured motion the stylesheet can't express: WAAPI animations (re-issued via
  *  element.animate), rotating text (interval-cycled), and scroll-triggered reveals (start
  *  hidden, transition in when scrolled into view). Starts on mount. Installs
@@ -133,6 +163,7 @@ export default function DittoMotion({ spec }: { spec: MotionSpec }) {
     const revealed: Array<(animate: boolean) => void> = [];
     let io: IntersectionObserver | null = null;
     let forceTimer: ReturnType<typeof setTimeout> | null = null;
+    const settleTimers: ReturnType<typeof setTimeout>[] = [];
 
     for (const w of spec.waapi) {
       const el = byCid(w.cid);
@@ -190,12 +221,14 @@ export default function DittoMotion({ spec }: { spec: MotionSpec }) {
         if (rv.visibility === "hidden") el.style.visibility = "visible";
         if (rv.animationName) {
           if (animate) {
-            // restart the entrance from t=0: none -> name starts a fresh animation
+            // restart the entrance from t=0: none -> name starts a fresh animation. Cap the
+            // delay + duration so the tile paints promptly after entering view (a long captured
+            // stagger/entrance would otherwise leave it blank through a fast scroll / screenshot).
             el.style.animationName = "none";
             void el.offsetWidth;
             el.style.animationName = rv.animationName;
-            el.style.animationDuration = rv.animationDuration || "1s";
-            el.style.animationDelay = rv.animationDelay || "0s";
+            el.style.animationDuration = clampDuration(rv.animationDuration);
+            el.style.animationDelay = clampDelay(rv.animationDelay);
             el.style.animationTimingFunction = rv.animationTiming || "ease";
             el.style.animationFillMode = "both";
             el.style.animationIterationCount = "1";
@@ -220,11 +253,22 @@ export default function DittoMotion({ spec }: { spec: MotionSpec }) {
         shows.set(el, fn);
         revealed.push(fn);
       }
+      // Per-element settle: a bounded time after a tile is animated in, force it to its settled
+      // frame (animate=false) so it can't be caught mid-entrance by a fast scroll / screenshot,
+      // regardless of when it entered view. The clamped delay+duration keep this window short.
+      const settleAfter = REVEAL_MAX_DELAY_MS + REVEAL_MAX_DURATION_MS + 100;
       io = new IntersectionObserver((entries) => {
-        for (const e of entries) if (e.isIntersecting) { const f = shows.get(e.target); if (f) { f(true); io!.unobserve(e.target); } }
+        for (const e of entries) if (e.isIntersecting) {
+          const f = shows.get(e.target); if (!f) continue;
+          f(true); io!.unobserve(e.target);
+          settleTimers.push(setTimeout(() => f(false), settleAfter));
+        }
       }, { rootMargin: "0px 0px -8% 0px" });
       for (const el of shows.keys()) io.observe(el);
-      forceTimer = setTimeout(() => { for (const f of revealed) f(true); }, 4000);
+      // Global failsafe: settle EVERYTHING (animate=false) so any element the observer never fired
+      // for (never scrolled into view, or a missed callback) is painted, not left hidden. Per-mount
+      // is sufficient because it jumps straight to the settled frame with no residual delay.
+      forceTimer = setTimeout(() => { for (const f of revealed) f(false); }, 4000);
     }
 
     const stopAll = () => {
@@ -234,6 +278,7 @@ export default function DittoMotion({ spec }: { spec: MotionSpec }) {
       for (const a of anims) { try { a.cancel(); } catch { /* ignore */ } }
       if (io) io.disconnect();
       if (forceTimer) clearTimeout(forceTimer);
+      for (const t of settleTimers) clearTimeout(t);
       for (const f of revealed) f(false); // reveal everything, settled → base CSS graded frame
     };
     // Measurement hook: restore the fully-settled/revealed base for grading.
@@ -242,6 +287,7 @@ export default function DittoMotion({ spec }: { spec: MotionSpec }) {
       for (const id of intervals) clearInterval(id);
       if (io) io.disconnect();
       if (forceTimer) clearTimeout(forceTimer);
+      for (const t of settleTimers) clearTimeout(t);
       try { delete (window as any).__dittoMotionStop; } catch { /* ignore */ }
     };
   }, [spec]);

compiler/src/validate/motionGate.ts

@@ -64,14 +64,26 @@ export function cssReplayedByReveal(
   return !!revealAnim && names.includes(revealAnim);
 }
 
-/** CSS-animated nodes expected from the IR (computed animation-name ≠ none). */
+/** A node's animation is scroll/view-timeline-driven when its computed animation-duration is
+ *  `auto` (the duration is resolved from the timeline range, not a time). The generator does NOT
+ *  emit such animations — replaying a scroll-linked animation is out of scope; the clone reproduces
+ *  the correct AT-REST state instead — so these are excluded from the static-CSS expectation rather
+ *  than failing `emitted=false`. Distinct from time-based reveals (finite duration, default timeline). */
+export function isScrollTimelineAnim(cs: IRNode["computedByVp"][number] | undefined): boolean {
+  const dur = cs?.animationDuration;
+  return !!dur && dur.split(",").some((d) => d.trim() === "auto");
+}
+
+/** CSS-animated nodes expected from the IR (computed animation-name ≠ none). Scroll/view-timeline
+ *  animations (animation-duration:auto) are excluded — the clone renders their at-rest state, not
+ *  a replay, so there is no static decl to expect. */
 export function collectExpectedCss(ir: IR): ExpectedCss[] {
   const vp = ir.doc.canonicalViewport;
   const out: ExpectedCss[] = [];
   const walk = (n: IRNode): void => {
     const cs = n.computedByVp[vp];
     const an = cs?.animationName;
-    if (an && an !== "none") {
+    if (an && an !== "none" && !isScrollTimelineAnim(cs)) {
       const names = an.split(",").map((x) => x.trim()).filter((x) => x && x !== "none");
       if (names.length) out.push({ cid: n.id, names, infinite: /infinite/.test(cs!.animationIterationCount ?? "") });
     }

compiler/test/css.test.ts

@@ -233,3 +233,60 @@ describe("generateCss hidden-node banded geometry", () => {
     assert.ok(!mobile.includes("left:10px"), `ancestor-hidden child must not emit geometry, got: ${mobile}`);
   });
 });
+
+// Fix 1 — mobile nav chip-strip overlap. A horizontally-scrollable flex strip (overflow-x:auto
+// flex <ul>) holds nowrap chips; the base viewport can report `min-width:0px` on those flex-item
+// chips (e.g. a mobile-only strip collapsed to 0 at desktop). Emitting `min-w-0` lets the chips
+// compress below their content width instead of overflowing, collapsing the scroll strip so the
+// nowrap chip text collides ("Pizza OvenSpiral Mixe…"). The emitter must suppress `min-w-0` for a
+// nowrap flex item inside an overflow-x:auto/scroll flex parent.
+describe("generateCss scroll-strip chip min-width", () => {
+  it("suppresses min-w-0 on a nowrap chip inside an overflow-x:auto flex strip", () => {
+    const chip = node("n2", "li", computed({ display: "list-item", minWidth: "0px", whiteSpace: "nowrap" }));
+    const ul = node("n1", "ul", computed({ display: "flex", overflowX: "auto", columnGap: "8px" }), [chip]);
+    const root = node("n0", "body", computed(), [ul]);
+    const css = generateCss(irWith(root), new Map());
+    assert.ok(!baseRule(css, "n2").includes("min-width"), `chip must not carry min-width:0 in a scroll strip, got: ${baseRule(css, "n2")}`);
+  });
+
+  it("still emits min-w-0 for a nowrap flex item whose parent does NOT scroll horizontally", () => {
+    // A truncation/ellipsis flex child (parent overflow-x:visible) legitimately needs min-w-0 to
+    // shrink below content — the fix is scoped to overflow-x:auto/scroll parents, so this is kept.
+    const item = node("n2", "div", computed({ minWidth: "0px", whiteSpace: "nowrap", overflow: "hidden", textOverflow: "ellipsis" }));
+    const row = node("n1", "div", computed({ display: "flex" }), [item]);
+    const root = node("n0", "body", computed(), [row]);
+    const css = generateCss(irWith(root), new Map());
+    assert.ok(baseRule(css, "n2").includes("min-width:0"), `non-scrolling flex row keeps min-w-0, got: ${baseRule(css, "n2")}`);
+  });
+});
+
+// Fix 3 — scroll-linked text-fill frozen at end state. A scroll/view-timeline animation reports
+// its resolved `animation-duration` as `auto`. The clone has no scroll timeline, so emitting the
+// animation-* props makes it jump straight to its END keyframe (fill-mode:both + a 0s time-based
+// duration), freezing e.g. a text-fill 100% filled at rest. The emitter must suppress the
+// animation-* longhands when animation-duration is `auto`, leaving the captured at-rest statics.
+describe("generateCss scroll-timeline animation suppression", () => {
+  it("drops animation-* props for an animation-duration:auto (scroll-timeline) node", () => {
+    const em = node("n1", "em", computed({
+      animationName: "fillAnimation", animationDuration: "auto",
+      animationTimingFunction: "linear", animationFillMode: "both",
+      backgroundClip: "text",
+    }));
+    const root = node("n0", "body", computed(), [em]);
+    const css = generateCss(irWith(root), new Map());
+    const rule = baseRule(css, "n1");
+    assert.ok(!rule.includes("animation-name"), `scroll-timeline node must not emit animation-name, got: ${rule}`);
+    assert.ok(!rule.includes("animation-duration"), `scroll-timeline node must not emit animation-duration, got: ${rule}`);
+  });
+
+  it("still emits animation-* for a normal time-based (finite duration) animation", () => {
+    const el = node("n1", "div", computed({
+      animationName: "fadeInUp", animationDuration: "1.25s",
+      animationTimingFunction: "ease", animationFillMode: "both",
+    }));
+    const root = node("n0", "body", computed(), [el]);
+    const css = generateCss(irWith(root), new Map());
+    const rule = baseRule(css, "n1");
+    assert.ok(rule.includes("animation-name:fadeInUp"), `time-based reveal keeps its animation, got: ${rule}`);
+  });
+});

compiler/test/motionGate.test.ts

@@ -9,7 +9,7 @@ import { missingHarnessDeps } from "../src/validate/render.js";
 
 // Minimal IRNode factory — collectExpectedCss only reads id, computedByVp[vp].animation*,
 // and children, so we build just those fields and cast.
-function node(id: string, anim: { animationName?: string; animationIterationCount?: string } | null, children: IRNode[] = []): IRNode {
+function node(id: string, anim: { animationName?: string; animationIterationCount?: string; animationDuration?: string } | null, children: IRNode[] = []): IRNode {
   return {
     id,
     tag: "div",
@@ -44,6 +44,20 @@ describe("motion gate — CSS entrance / reveal-replay accounting", () => {
     assert.deepEqual(fade.names, ["fadeInUp"]);
   });
 
+  it("collectExpectedCss EXCLUDES a scroll/view-timeline animation (animation-duration:auto)", () => {
+    // Fix 3: the ooni text-fill em (animation-timeline:view → computed animation-duration:auto)
+    // is intentionally NOT emitted (we render the at-rest state, not a scroll replay). It must be
+    // excluded from the static-CSS expectation, not counted as an owed-but-missing animation.
+    const tree = ir(
+      node("n0", null, [
+        node("n358", { animationName: "fillAnimation", animationDuration: "auto", animationIterationCount: "1" }),
+        node("n4", { animationName: "spin", animationDuration: "1s", animationIterationCount: "infinite" }),
+      ]),
+    );
+    const got = collectExpectedCss(tree);
+    assert.deepEqual(got.map((e) => e.cid), ["n4"], "scroll-timeline node n358 must be excluded");
+  });
+
   it("cssReplayedByReveal excludes a captured entrance the clone replays via a reveal", () => {
     // The cropin regression: n464's fadeInUp is driven by a DittoMotion reveal, so the static
     // animation-name is deliberately NOT emitted — it must NOT fail emitted=false.

compiler/test/reveal.test.ts

@@ -132,4 +132,25 @@ describe("scroll-reveal settling + replay capture (integration)", () => {
     // Validator settle path reveals WITHOUT replaying (no mid-entrance graded frames).
     assert.match(DITTO_MOTION_TSX, /f\(false\)/);
   });
+
+  // Fix 2 — reveal-replay stagger must not leave tiles unpainted. A long captured entrance
+  // delay/duration replayed on scroll-into-view means a fast scroll / full-page screenshot
+  // catches most tiles mid-entrance. The replay caps the delay + duration and force-settles
+  // each tile shortly after it enters view, so tiles paint promptly and none stay hidden.
+  it("caps the replayed entrance delay and duration", () => {
+    // The animate path uses the clamp helpers rather than the raw captured values.
+    assert.match(DITTO_MOTION_TSX, /el\.style\.animationDuration = clampDuration\(rv\.animationDuration\)/);
+    assert.match(DITTO_MOTION_TSX, /el\.style\.animationDelay = clampDelay\(rv\.animationDelay\)/);
+    // Caps are bounded (delay <= 300ms, duration <= 600ms).
+    assert.match(DITTO_MOTION_TSX, /REVEAL_MAX_DELAY_MS = 300/);
+    assert.match(DITTO_MOTION_TSX, /REVEAL_MAX_DURATION_MS = 600/);
+  });
+
+  it("force-settles each revealed tile per-element and settles everything at the failsafe", () => {
+    // Per-element settle timer jumps a tile to its settled frame a bounded time after it animates
+    // in (so it can't be caught mid-entrance regardless of WHEN it scrolled into view).
+    assert.match(DITTO_MOTION_TSX, /settleTimers\.push\(setTimeout\(\(\) => f\(false\), settleAfter\)\)/);
+    // Global failsafe settles (animate=false) rather than re-animating — nothing stays hidden.
+    assert.match(DITTO_MOTION_TSX, /forceTimer = setTimeout\(\(\) => \{ for \(const f of revealed\) f\(false\); \}, 4000\)/);
+  });
 });