feat(studio): instant, flicker-free manual editing (#1605)

* chore(producer): shim __filename/__dirname in the CJS banner Bundled CJS deps like wawoff2 call __dirname; without the shim they throw "__dirname is not defined in ES module" at render time. Also ignore .zed/. * chore(producer): use a template literal for the CJS banner (review nit) * feat(core): add GSAP keyframe + motion-path source mutations Array-form keyframe removal in both the recast and acorn writers, plus update/add/remove-motion-path-point and add-motion-path. Exclude _auto and data from tween property-group classification. * fix(core): address #1554 review — data-exclusion test, split-fix doc, motion-path sentinel, parity blocks - Regression test for the `data` GSAP-key exclusion (parallel to _auto). - splitAnimationsInScript: documented that .fromTo()/.to() correctly stay out of the from-branch (only .from() reverts) and the <= boundary; added mid-flight straddle tests. - addMotionPathToScript failure path returns id: null (was empty-string sentinel); caller updated. - Parity blocks for addKeyframeToScript array-form + updateKeyframeInScript (mirroring removeKeyframeFromScript). Surfaced a latent acorn array-form partial-props merge bug — documented as it.skip with a ready assertion (acorn cutover follow-up). * feat(core): route motion-path mutations through studio-api + fix clip stamping Wire the new mutations into the file save route. Only authored clips suppress descendant stamping, so auto-stamped animated scenes can inline-expand. Hide in-flow timed clips with `display:none` only when they are LEAF clips (no nested timed clips). `display:none` on a container removes its whole subtree, hiding descendants that are still inside their own visibility window — e.g. an in-flow composition root whose effective window clamps to the timeline end would black out a child video that should still show (the hdr-hlg regression). Containers keep `visibility:hidden`, which a visible descendant can override; only leaves leave the flow, which is all the split-overlap case needs. * feat(core): strip legacy path-offset/rotation + drop obsolete studio lint rule A position or rotation add/set mutation makes the GSAP timeline the single source of truth for that channel, so any lingering --hf-studio-offset / --hf-studio-rotation CSS var must be cleared to avoid double-applying. stripStudioEditsFromTarget now clears both channels, and the add-strip fires for the position AND rotation property groups. Also removes the obsolete `gsap_studio_edit_blocked` lint rule: it warned that Studio cannot save drag/resize edits to elements in a registered timeline — the exact premise the single-source work inverts (the timeline is now the edit target). Removed the rule, its now-unused TIMELINE_REGISTRY_ASSIGN_PATTERN import, and its 5 tests. * fix(core): address #1555 review — complete hold-sync, invalidate clip cache, strip rotation channel - HOLD_SYNC_MUTATION_TYPES: add add-motion-path (load-bearing — addMotionPathToScript authors past t=0 → first-frame snap-to-(0,0) without the hold), update-meta, shift-positions, scale-positions, split-animations. (add stays out: flat tweens only, syncPositionHoldsBeforeKeyframes is a no-op for non-keyframed tweens.) - init.ts: timedClip in-flow/leaf WeakMaps now invalidate on clipTreeSignature change; visible/hidden branches both go through isTimedClipInFlow (was .get() by accident). - keyframesWriteRotation mirrors keyframesWritePosition so a rotation-only keyframe set strips the stale --hf-studio-rotation channel. * feat(studio): GSAP runtime read layer + shared helpers * fix(studio): address #1607 review — cold-parse vs fetch-error budgets, isZeroDurationSet, array-ease tests - useGsapAnimationFetchFallback: discriminate resolved/fetch-error/cold; only the cold (warm-but-zero) race gets the full ~600ms retry budget — a hard fetch error retries once. - Extract isZeroDurationSet (was !(duration>0) duplicated); rejects NaN, documents intent. - parsePercentageKeyframes: cite GSAP even-index spread; tests that a per-entry/interior ease is stripped without shifting the other keyframes' percentages. * feat(studio): GSAP drag/commit/bridge editing infra * fix(studio): address #1608 review — facade awaits commit, strict stale-parse guard, clearProps restore BLOCKER: useSafeGsapCommitMutation now RETURNS the (.catch-chained) commit promise and the commitMutation facade awaits it — so await session.commitMutation(...) resolves AFTER the server save, fixing both consumers (useEnableKeyframes + useGestureCommit's showToast/requestSeek/idle, which were firing before the save landed). SafeGsapCommitMutation return type widened void→Promise<void> (fire-and-forget consumers ignore it). - stale-parse guard uses hasNonHoldTweenForElement (a leftover hold set no longer counts as live). - commitFlatViaKeyframes snapshots dragged gsap values before clearProps + restores after seek, so a failed commit leaves the dropped pose, not a cleared element. * feat(studio): motion-path geometry + commit helpers * docs(studio): address #1609 review — document occlusion fade-in invariant, donut limit, nearestPointOnPath t-semantics * feat(studio): on-canvas motion-path overlay * fix(studio): address #1610 review — scope dblclick to pan-surface, kind-aware geometry guard, gate createMode, screen-space drag threshold * feat(studio): keyframes flag, gesture recording + timeline/selection refinements * fix(studio): address #1611 review — fetch-first keyframe path, gated hydration, dev-gated debug + gesture warn, per-group gesture tweens - useEnableKeyframes: parse current source first (null-vs-[] distinction) so a delete-all's empty parse isn't overridden by a stale selectedGsapAnimations cache. - useStudioUrlState: freeze the hydration effect's time dep once hydrated (was re-running every tick). - useGestureRecording: dev-gated console.warn when the live-preview runtime throws (was silent). - playerStore: gate window.__playerStore behind dev (guarded import.meta.env.DEV). - useGestureCommit: partition recorded keyframes by property group → one add-with-keyframes per group, so a mixed gesture no longer yields an untagged legacy tween. * feat(studio): single-source manual offset + rotation via the GSAP timeline Dragging or rotating an element writes into the GSAP timeline (the single source of truth) instead of a parallel --hf-studio-offset / --hf-studio-rotation CSS var: static elements commit a tl.set (idempotent on re-edit), tweened elements edit keyframes, and the live preview moves via gsap.set so what you see equals what is written and renders. Removes the dual-channel CSS-var/transform reconciliation behind the fling / disappear / runaway / double-stack / wrong-start bug class — for BOTH position and rotation (gesture base read from the gsap transform, gsap.set live preview, tl.set/ keyframe commit, dropped the handleDom*Commit CSS fallbacks). Subcompositions edit the same single-source way, which surfaced and fixes: - resolve a subcomp element's source file via the composition-id map (the runtime drops the source linkage when inlining the subcomposition); - a selected element's selection box AND motion path use basic visibility, not the occlusion heuristic (a backgroundless opacity-1 scene above it is not an opaque cover); - soft reload rebuilds ONLY the committed composition's timeline, leaving other compositions' timelines intact (no cross-composition revert); - read keyframes from the element's OWN composition timeline (scan all timelines, not the first unstable key); - delete-all uses a soft reload too, so editing no longer hard-reloads the iframe. * fix(studio): address #1567 review — drop drag-intercept flag, harden softReload onerror, tighten runtime ladder, per-group gestures - DROP STUDIO_GSAP_DRAG_INTERCEPT_ENABLED: single-source GSAP intercept is the only position/rotation channel; the false branch silently killed drag+rotate (and let GSAP elements into the keyframe-corrupting CSS path). Removed flag + dead branch + env def + tests. - gsapSoftReload: plugin onerror no longer fakes success — signals onAsyncFailure so the caller full-reloads; honors __hfMotionPathPluginLoading so a concurrent reload can't queue a dup script. - gsapDragCommit: resolveDragRuntime narrows the as-any ladder; a mid-seek throw logs + drops partial reads (no phantom identity) and re-applies the drag override in finally. - MotionPathOverlay: park-timer cleanup keyed on animId change. - useGestureCommit: partitionKeyframesByGroup wraps the add-with-keyframes sites (per #1611 review). * feat(studio): patchRuntimeTweenInPlace — update a tween's values in place Defensive runtime helper: locate the element's tween in window.__timelines via the shared resolveRuntimeTween scan, update its set/keyframe vars, invalidate, and re-seek the playhead — without re-running the whole composition. Returns false (caller falls back to soft reload) for any shape it can't safely patch (no tween, dynamic/computed keyframes, motionPath arc, channel mismatch, or any error). Foundation for instant, flicker-free manual edits. * fix(studio): address #1612 review — channel-aware set resolution + decline dynamic-expression patches - resolveRuntimeTween gains an optional channels[] hint; for kind:set it prefers the set whose vars carry one of the patched channels and never returns a disjoint-only set (e.g. won't write {x,y} into a co-located {rotation} set). patchRuntimeTweenInPlace derives channels from the props. - patchSet declines (returns false → soft reload) when overwriting a string/dynamic vars[ch], instead of silently dropping the computed expression. * feat(studio): instantPatch fast path in runCommit A commit carrying an instantPatch option tries patchRuntimeTweenInPlace first; on success the preview updates in place with NO reload (instant), on false it falls back to the existing soft reload. Extracts the preview-sync tail into a testable applyPreviewSync helper. No behavior change when instantPatch is absent. * feat(studio): route static position/rotation set drags through instantPatch Static-element position and rotation set commits now attach instantPatch{selector, change:{kind:set}} so the drag updates in place with no reload. Structural ops (new tween add, delete-all, convert/split/materialize) and keyframe edits deliberately omit it and keep the soft reload — keyframe instant-patch needs object-form keyframe support in patchRuntimeTweenInPlace (deferred). * fix(studio): address #1613 review — derive instantPatch from the mutation, patch both coalesced commits, wire onAsyncFailure - commitStaticGsapPosition/Rotation derive instantPatch.change.props from the actual update-property mutation(s) sent (one source of truth → findUnsafeMutationValues-validated values flow into the patch; can't drift). - Coalesced x/y: the intermediate x commit also carries instantPatch{x}, the y commit {x,y}, so a second-POST failure still leaves the preview patched for what persisted. - applyPreviewSync passes reloadPreview as onAsyncFailure (plugin-CDN load error → full reload); per U4 the synchronous false still does NOT escalate. - (channel disambiguation from #1612 verified end-to-end: {x,y}→position set, {rotation}→rotation set.) * feat(studio): no full iframe remount for soft-reloadable edits A softReload edit (and the SDK single-script refresh) no longer escalates to a full reloadPreview() iframe remount when applySoftReload returns false — the live gsap.set already shows the value, and a remount is the worst flash + re-inlines subcomps (reverting their keyframes). verifyTimelinesPopulated now checks the expected target keys the re-run registers, so a correct scoped re-run doesn't spuriously report empty. Full reload stays only for the structural (no-softReload) and ambiguous-script paths. * feat(studio): pre-load MotionPathPlugin so motion-path edits don't async-flash ensureMotionPathPluginLoaded() runs once at the preview iframe-load seam (NLELayout onIframeLoad), eagerly loading + registering MotionPathPlugin without killing the timeline. So when a user adds a motion path to a composition that didn't originally use one, the soft reload runs synchronously instead of taking the kill-then-await-CDN async path (the flash). Idempotent + defensive; the existing async fallback stays for genuine cold-start/CDN-failure. * fix(studio): don't re-save + reload when source editor syncs externally The SourceEditor's CodeMirror update listener fired onChange on ANY docChanged — including the programmatic dispatch that syncs external content (e.g. a manual-edit commit writing the source back into the open editor). That made the editor re-save the file and bump refreshKey, fully reloading the preview iframe on every drag/keyframe edit — defeating the in-place instant patch and causing the flash. Annotate the programmatic sync (ExternalSync) and skip onChange for it, so only real keystrokes save. * fix(core): inject MotionPathPlugin into preview when a composition uses motionPath A studio-created motion path writes a gsap motionPath tween into the single-source timeline, but the preview HTML only loaded gsap core — so the first render threw "Invalid property motionPath ... Missing plugin?". Detect motionPath usage and inject MotionPathPlugin right after the composition's gsap script, version-matched to it. * fix(studio): dedup __hfMotionPathPluginLoading type decl (restack artifact) * fix(studio): address #1605 review — distinguish soft-reload failure modes + observability, SourceEditor focus guard BLOCKER: applySoftReload now returns SoftReloadResult ('applied' | 'verify-failed' | 'cannot-soft-reload') instead of a bare bool. applyPreviewSync + sdkRefresh escalate to a full reloadPreview() on the PERMANENT 'cannot-soft-reload' (no gsap/rebind hook/scopable key/script, or sync re-run threw) — fixing the silent-stale-preview U4 dropped — but still suppress the TRANSIENT 'verify-failed' (live gsap.set is correct). Telemetry: gsap_soft_reload_outcome (origin/result/escalated) + gsap_instant_patch_fallback, so the U4 invariant is enforced, not asserted. - SourceEditor: skip the programmatic external-sync replace while the editor is focused, so an in-flight commit doesn't clobber the user's uncommitted keystrokes (ExternalSync kept for unfocused). - Verified ensureMotionPathPluginLoaded already guards __hfMotionPathPluginLoading (no double-append). * fix(core): align __clipTree and __clipManifest ids via stableClipId Timeline inline expansion was dead for nested children inside index.html: the tree keyed id-less elements by a synthetic __clip-N while the manifest keyed them null, so parent<->child never joined. Both now resolve identity through stableClipId (id || data-hf-id), which every generated element has. * fix(core): strip baked runtime + tag comp root in preview assembly Comps that ship a baked inline runtime were double-loaded (preview injects its own) and the baked copy failed to parse inline (Unexpected token '<'). Strip it in buildSubCompositionHtml + the disk-fallback preview path. Also tag the comp root with data-composition-file so the studio resolves a comp's top-level elements to the right source file instead of defaulting to index.html (which made the GSAP panel parse the wrong, multi-timeline file). * feat(studio): set motion-path destination from a toolbar toggle Replaces the double-click-on-canvas UX (which painted text over the preview) with a 'Set motion destination' toggle next to Snap/Grid, shown only when the selected element can take a path. While armed, one canvas press places the destination. Also removes the dead TimelinePropertyRows component. * fix(studio): center timeline keyframe diamonds on their percentage Dropped clampDiamondLeft, which forced boundary keyframes fully inside the clip so a 0% diamond sat half a diamond right of the 0% point. Each diamond's midpoint now sits exactly on its % (the clip is overflow-visible). * fix(studio): resize static elements via tl.set, not a single-stop keyframes tween Resizing an element with no size animation wrote keyframes:{ <playhead%>: {width,height} } — one mid-point stop GSAP can't interpolate, so it rendered NaN/0 dimensions at every other frame and the element vanished (worst off 0%). Added commitStaticGsapSize (mirrors commitStaticGsapPosition): a static resize now writes tl.set({width,height}), held at all frames; re-resizing updates it in place. * fix(studio): negative-cache failed media probes Only successful probes were cached, so CORS/404 cross-origin media was re-probed every rAF-driven timeline re-derive, flooding the console. Remember failed URLs and skip them. * fix(studio): type window.setTimeout handle as number ReturnType<typeof window.setTimeout> infers NodeJS.Timeout when @types/node is present and clashes with the DOM number the call returns. Type it number. * fix(studio): drag/resize disappearance, stale-ID duplicates, soft-reload clearProps - Fix soft-reload clearProps destroying element inline styles — save cssText, clear, restore, strip only transform - Fix resize no-op on re-resize: delete+add instead of two update-property - Route set tweens through static resize path (convertToKeyframes skips sets) - Re-fetch animation ID before drag commit to prevent stale-ID duplicates - Guard editDebugLog for Node test environments - Fix NLELayout setState-during-render (move reset to useEffect) - Stop SnapToolbar pointer events propagating to canvas deselect handler - Enable click-to-add waypoints on cubic motion paths - Add whole-path drag offset (Alt+drag shifts all keyframes together) - Add Canvas shortcuts section to ShortcutsPanel - Extract useMotionPathData + commitGsapPositionFromDrag (filesize compliance) - Delete dead code (getElementDepth, isElementVisibleInPreview, unused exports)
2026-09-04 07:19:52 +00:00 · 2026-06-22 01:21:18 -04:00
parent e0822c6e85
commit 091137e3c3
103 changed files with 8012 additions and 1217 deletions
@@ -12,20 +12,23 @@ import { buildArcPath, type ArcPathConfig } from "@hyperframes/core/gsap-parser-
 import { parsePercentageKeyframes, toAbsoluteTime } from "./gsapShared";
 import { roundTo3 } from "../utils/rounding";

-interface RuntimeTween {
+export interface RuntimeTween {
  targets?: () => Element[];
  vars?: Record<string, unknown>;
  duration?: () => number;
  startTime?: () => number;
+  invalidate?: () => RuntimeTween;
 }

-interface RuntimeTimeline {
+export interface RuntimeTimeline {
  getChildren?: (deep: boolean) => RuntimeTween[];
  duration?: () => number;
+  time?: () => number;
+  invalidate?: () => RuntimeTimeline;
 }

 type Pct = { percentage: number; properties: Record<string, number | string> };
-type ReadTween = { keyframes: Pct[]; easeEach?: string; arcPath?: ArcPathConfig };
+export type ReadTween = { keyframes: Pct[]; easeEach?: string; arcPath?: ArcPathConfig };

 export interface RuntimeKeyframeEntry {
  keyframes: Pct[];
@@ -71,6 +74,17 @@ function isXY(p: unknown): p is { x: number; y: number } {
  return !!p && typeof (p as any).x === "number" && typeof (p as any).y === "number";
 }

+/**
+ * A tween we must skip when reading keyframes: a zero-duration `set`/hold (incl.
+ * the studio pre-keyframe position hold, tagged `data: STUDIO_HOLD_MARKER`).
+ * These sit before the real keyframed tween and otherwise shadow it — `readTween`
+ * would fall back to a degenerate 2-point flat path from the set's values, hiding
+ * the actual multi-keyframe motion. `!(duration > 0)` also rejects NaN durations.
+ */
+function isZeroDurationSet(duration: number): boolean {
+  return !(duration > 0);
+}
+
 /** Coordinates + curviness from a live `vars.motionPath` value (object or array form), or null. */
 function coordsFromMotionPath(mp: unknown): {
  coords: Array<{ x: number; y: number }>;
@@ -149,6 +163,95 @@ function tweenTiming(tween: RuntimeTween): { start: number; duration: number } {
  };
 }

+export interface ResolvedRuntimeTween {
+  /** The live GSAP tween targeting the selector. */
+  tween: RuntimeTween;
+  /** The composition timeline that owns it. */
+  timeline: RuntimeTimeline;
+}
+
+/**
+ * Whether a tween's `vars` carry at least one of `channels` as an OWN property.
+ * Used to disambiguate co-located `set`s: an element can have separate
+ * `tl.set("#el",{x,y})` and `tl.set("#el",{rotation})` tweens, and a position
+ * patch must land on the {x,y} set — never the rotation-only one.
+ */
+function varsCarryChannel(vars: Record<string, unknown> | undefined, channels: string[]): boolean {
+  if (!vars) return false;
+  for (const ch of channels) {
+    if (Object.prototype.hasOwnProperty.call(vars, ch)) return true;
+  }
+  return false;
+}
+
+/**
+ * Resolve the live tween targeting `selector` using the SAME all-timelines scan
+ * `readRuntimeKeyframes` uses, so read and write agree on "which tween". With
+ * `kind: "keyframe"` it skips zero-duration `set`s and prefers the tween whose
+ * range contains the playhead (matching the reader). With `kind: "set"` it picks
+ * the zero-duration `set`/hold instead. Returns null when none matches.
+ *
+ * `channels` disambiguates co-located `set`s (CHANNEL-BLIND otherwise): when
+ * provided with `kind: "set"`, a set carrying ONE of those channels wins, and a
+ * set carrying ONLY disjoint channels is skipped (so patching {x,y} never lands
+ * on a rotation-only set). With no channel-matching set, it falls back to the
+ * first matching set (back-compat). `channels` is ignored for `kind: "keyframe"`.
+ */
+export function resolveRuntimeTween(
+  iframe: HTMLIFrameElement | null,
+  selector: string,
+  kind: "keyframe" | "set",
+  compositionId?: string,
+  channels?: string[],
+): ResolvedRuntimeTween | null {
+  const timelines = timelinesOf(iframe);
+  if (!timelines) return null;
+
+  let targetEl: Element | null = null;
+  try {
+    targetEl = iframe?.contentDocument?.querySelector(selector) ?? null;
+  } catch {
+    return null;
+  }
+  if (!targetEl) return null;
+
+  const tlIds = compositionId
+    ? [compositionId]
+    : Object.keys(timelines).filter((k) => typeof timelines[k]?.getChildren === "function");
+
+  const wantChannels = kind === "set" && channels && channels.length > 0 ? channels : null;
+
+  let first: ResolvedRuntimeTween | null = null;
+  let channelMatch: ResolvedRuntimeTween | null = null;
+  for (const tlId of tlIds) {
+    const timeline = timelines[tlId];
+    if (!timeline?.getChildren) continue;
+    const now = typeof timeline.time === "function" ? timeline.time() : null;
+    for (const tween of timeline.getChildren(true)) {
+      if (!tween.vars || !matchesElement(tween, targetEl)) continue;
+      const dur = typeof tween.duration === "function" ? tween.duration() : 0;
+      const isSet = !(dur > 0);
+      if (kind === "set" ? !isSet : isSet) continue;
+      if (wantChannels) {
+        if (varsCarryChannel(tween.vars, wantChannels)) {
+          if (channelMatch === null) channelMatch = { tween, timeline };
+        } else if (first === null) {
+          // A set carrying only disjoint channels: remember as last-resort
+          // fallback, but never prefer it over a channel-matching set.
+          first = { tween, timeline };
+        }
+        continue;
+      }
+      if (first === null) first = { tween, timeline };
+      if (kind === "keyframe" && now != null) {
+        const start = typeof tween.startTime === "function" ? tween.startTime() : 0;
+        if (now >= start - 1e-3 && now <= start + dur + 1e-3) return { tween, timeline };
+      }
+    }
+  }
+  return channelMatch ?? first;
+}
+
 /**
 * Read keyframes (incl. motionPath arcs) for one selector from the live timeline.
 * Returns tween-relative percentages; callers convert to clip-relative.
@@ -160,10 +263,6 @@ export function readRuntimeKeyframes(
 ): ReadTween | null {
  const timelines = timelinesOf(iframe);
  if (!timelines) return null;
-  const tlId = compositionId || Object.keys(timelines)[0];
-  if (!tlId) return null;
-  const timeline = timelines[tlId];
-  if (!timeline?.getChildren) return null;

  let targetEl: Element | null = null;
  try {
@@ -173,12 +272,84 @@ export function readRuntimeKeyframes(
  }
  if (!targetEl) return null;

+  // Search the element's OWN composition timeline. With inlined subcompositions the
+  // preview has multiple timelines (one per composition), and the element belongs to
+  // exactly one — so we can't assume the first key (order isn't stable across soft
+  // reloads, which delete+re-add the rebuilt key). Scan every timeline for tweens
+  // targeting this element; only its composition's timeline matches. An explicit
+  // compositionId still pins the search. (`__proxied` and other non-timeline markers
+  // are skipped by the getChildren guard.)
+  const tlIds = compositionId
+    ? [compositionId]
+    : Object.keys(timelines).filter((k) => typeof timelines[k]?.getChildren === "function");
+  if (tlIds.length === 0) return null;
+
+  // The element can have MORE THAN ONE keyframed tween at disjoint time ranges
+  // (e.g. two non-overlapping gesture recordings → two separate `to()`s). The
+  // overlay must draw the segment under the PLAYHEAD, not blindly the first one
+  // — otherwise recording a second gesture leaves the path stuck on the first.
+  let firstRead: ReadTween | null = null;
+  for (const tlId of tlIds) {
+    const timeline = timelines[tlId];
+    if (!timeline?.getChildren) continue;
+    const now = typeof timeline.time === "function" ? timeline.time() : null;
+    for (const tween of timeline.getChildren(true)) {
+      if (!tween.vars || !matchesElement(tween, targetEl)) continue;
+      const dur = typeof tween.duration === "function" ? tween.duration() : 0;
+      if (isZeroDurationSet(dur)) continue; // skip hold/set tweens (see isZeroDurationSet)
+      const read = readTween(tween.vars);
+      if (!read) continue;
+      if (firstRead === null) firstRead = read;
+      // Prefer the tween whose [start, start+dur] contains the playhead.
+      if (now != null) {
+        const start = typeof tween.startTime === "function" ? tween.startTime() : 0;
+        if (now >= start - 1e-3 && now <= start + dur + 1e-3) return read;
+      }
+    }
+  }
+  // Playhead outside every tween's range (or timeline has no clock): the element
+  // still has motion, so fall back to the first keyframed tween.
+  return firstRead;
+}
+
+/**
+ * Whether the live timeline has at least one NON-HOLD tween (non-zero duration,
+ * not the studio position-hold `set`) targeting `selector`. Stricter than a
+ * truthy `readRuntimeKeyframes`: that returns a flat read for any property-bearing
+ * tween, so it can't distinguish a real animation from a leftover hold/marker.
+ * The drag's stale-parse guard needs this exact distinction — after a delete-all
+ * only a hold may remain, and resurrecting the deleted tween from the stale parse
+ * must be avoided.
+ */
+export function hasNonHoldTweenForElement(
+  iframe: HTMLIFrameElement | null,
+  selector: string,
+  compositionId?: string,
+): boolean {
+  const timelines = timelinesOf(iframe);
+  if (!timelines) return false;
+  const tlId =
+    compositionId ||
+    Object.keys(timelines).find((k) => typeof timelines[k]?.getChildren === "function");
+  if (!tlId) return false;
+  const timeline = timelines[tlId];
+  if (!timeline?.getChildren) return false;
+
+  let targetEl: Element | null = null;
+  try {
+    targetEl = iframe?.contentDocument?.querySelector(selector) ?? null;
+  } catch {
+    return false;
+  }
+  if (!targetEl) return false;
+
  for (const tween of timeline.getChildren(true)) {
    if (!tween.vars || !matchesElement(tween, targetEl)) continue;
-    const read = readTween(tween.vars);
-    if (read) return read;
+    const dur = typeof tween.duration === "function" ? tween.duration() : 0;
+    if (isZeroDurationSet(dur)) continue; // skip hold/set tweens (see isZeroDurationSet)
+    if (readTween(tween.vars)) return true;
  }
-  return null;
+  return false;
 }

 /** Convert tween-relative keyframes to clip-relative % using the element's clip dims. */
@@ -217,9 +388,10 @@ function addScanEntry(
  clipById?: ClipDims,
 ): void {
  if (!tween.targets || !tween.vars) return;
+  const { start, duration } = tweenTiming(tween);
+  if (isZeroDurationSet(duration)) return; // skip hold/set tweens (see isZeroDurationSet)
  const read = readTween(tween.vars);
  if (!read) return;
-  const { start, duration } = tweenTiming(tween);
  for (const target of tween.targets()) {
    const id = (target as HTMLElement).id;
    if (id && !result.has(id)) result.set(id, buildEntry(read, start, duration, clipById?.get(id)));