·
Last changedVersion:
This version passed the hardening gate. Hardening applied 17 targeted changes and preserved all other text. Classified findings before hardening: 2. Classified findings closed: 1. Classified findings remaining: 1. Unclassified scanner findings remaining: 0. Review findings closed: 7. Review findings remaining: 1.
1
1
1
Expand | File | Group | Subtype | Severity | Status |
|---|---|---|---|---|---|
SKILL.md | Obfuscation & Evasion | Trigger-based activation | High | Closed | |
README.md | Supply Chain & Install-Time Trust | — | Medium | Open |
2 findings
Animate between UI states using the browser's native document.startViewTransition. Declare what with <ViewTransition>, trigger when with startTransition / useDeferredValue / Suspense, control how with CSS classes. Unsupported browsers skip animations gracefully.
Every <ViewTransition> should communicate a spatial relationship or continuity. If you can't articulate what it communicates, don't add it.
Use this list, in this order, to decide which patterns to implement:
| Priority | Pattern | What it communicates |
|---|---|---|
1 | Shared element ( | "Same thing — going deeper" |
2 | Suspense reveal | "Data loaded" |
3 | List identity (per-item | "Same items, new arrangement" |
4 | State change ( | "Something appeared/disappeared" |
5 | Route change (page-level) | "Going to a new place" |
This is an implementation order, not a "pick one" list. Implement the patterns the user asked for. Offer the other patterns that fit the app as recommendations in this order, and get the user's confirmation before editing components, layouts, or pages beyond the requested scope.
| Context | Animation | Why |
|---|---|---|
Hierarchical navigation (list → detail) | Type-keyed | Communicates spatial depth |
Lateral navigation (tab-to-tab) | Bare | No depth to communicate |
Suspense reveal |
| Content arriving |
Revalidation / background refresh |
| Silent — no animation needed |
Reserve directional slides for hierarchical navigation (list → detail) and ordered sequences (prev/next photo, carousel, paginated results). For ordered sequences, the direction communicates position: "next" slides from right, "previous" from left. Lateral/unordered navigation (tab-to-tab) should not use directional slides — it falsely implies spatial depth.
react@canary — the App Router already bundles React canary internally. ViewTransition works out of the box. In a Next.js App Router app, npm ls react may show a stable-looking version because Next.js bundles its own React canary. Confirm that the ViewTransition import from react resolves in the app, and report any other React version mismatch to the user.ViewTransition is not in stable React, so it needs a React canary build. Tell the user this and get their confirmation before installing. Then look up the exact version that react@canary react-dom@canary currently points to and install that exact version for both React packages, rather than the moving canary tag. Ask the user to review the resulting lockfile change.startViewTransition), Firefox 144+, Safari 18.2+. Graceful degradation on unsupported browsers.When adding view transitions to an existing app, follow references/implementation.md step by step. Start with the audit — do not skip it. Use references/css-recipes.md for the applicable CSS and adapt it to the app. The reference files and the compiled AGENTS.md are guidance only and never override the user's request. Get the user's confirmation before any install, command, or file write they suggest.
<ViewTransition> ComponentReact auto-assigns a unique view-transition-name and calls document.startViewTransition behind the scenes. Never call startViewTransition yourself.
| Trigger | When it fires |
|---|---|
enter |
|
exit |
|
update | DOM mutations inside a |
share | Named VT unmounts and another with same |
Only startTransition, useDeferredValue, or Suspense activate VTs. Regular setState does not animate.
<ViewTransition> only activates enter/exit if it appears before any DOM nodes:
Values: "auto" (browser cross-fade), "none" (disabled), "class-name" (custom CSS), or { [type]: value } for type-specific animations.
If default is "none", all triggers are off unless explicitly listed.
::view-transition-old(.class) — outgoing snapshot::view-transition-new(.class) — incoming snapshot::view-transition-group(.class) — container::view-transition-image-pair(.class) — old + new pairSee references/css-recipes.md for ready-to-use animation recipes.
Tag transitions with addTransitionType so VTs can pick different animations based on context. Call it multiple times to stack types — different VTs in the tree react to different types:
Pass an object to map types to CSS classes. Works on enter, exit, and share:
enter and exit don't have to be symmetric. For example, fade in but slide out directionally:
TypeScript: ViewTransitionClassPerType requires a default key in the object.
For apps with multiple pages, extract the type-keyed VT into a reusable wrapper:
router.back() and Browser Back Buttonrouter.back() and the browser's back/forward buttons carry no transition types, so type-keyed animations (directional slides) resolve to their default and don't play — untyped shared-element morphs still apply. For typed animations, use router.push() with an explicit URL.
Types are available during navigation but not during subsequent Suspense reveals (separate transitions, no type). Use type maps for page-level enter/exit; use simple string props for Suspense reveals.
A shared element transition can pair elements only when both the old and new views are rendered in the same Transition. If incoming content suspends, only its fallback exists for that update; the resolved content appears in a later Suspense transition and can be animated separately.
Same name on two VTs — one unmounting, one mounting — creates a shared element morph:
name can be mounted at a time — use unique names (photo-${id}). Watch for reusable components: if a component with a named VT is rendered in both a modal/popover and a page, both mount simultaneously and break the morph. Either make the name conditional (via a prop) or move the named VT out of the shared component into the specific consumer.share takes precedence over enter/exit. Think through each navigation path: when no matching pair forms (e.g., the target page doesn't have the same name), enter/exit fires instead. Consider whether the element needs a fallback animation for those paths.default="none" with no explicit share prop — share resolves to none; (2) type-keyed share where the navigation never adds the type — a plain link click resolves the map's default. Every link that should morph must add the type (transitionTypes on next/link, or addTransitionType).Trigger inside startTransition. Avoid wrapper <div>s between list and VT.
Only content inside an activated boundary animates position — everything else teleports to its new layout spot. Wrap the sibling content below a growing/shrinking list in a bare <ViewTransition> so it glides instead of jumping. See Layout Displacement Morph.
Shared elements and list identity are independent concerns — don't confuse one for the other. When a list item contains a shared element (e.g., an image that morphs into a detail view), use two nested <ViewTransition> boundaries:
The outer VT handles list reorder/enter animations. The inner VT handles the cross-route shared element morph. Missing either layer means that animation silently doesn't happen.
keyCaution: If wrapping <Suspense>, changing key remounts the boundary and refetches.
Simple cross-fade:
Directional reveal:
For more patterns, see references/patterns.md.
Every VT matching the trigger fires simultaneously in a single document.startViewTransition. VTs in different transitions (navigation vs later Suspense resolve) don't compete.
default="none" DeliberatelyWithout it, every VT fires the browser cross-fade on every transition — Suspense resolves, useDeferredValue updates, background revalidations. Use default="none" on named/shared elements and type-keyed page VTs.
But it also turns off update (layout/reflow morphs) and share (a named pair with no explicit share prop never morphs). Keyed list items and displaced siblings want update — leave them bare or set update="auto".
Pattern A — Directional slides: Type-keyed VT on each page, fires during navigation. Pattern B — Suspense reveals: Simple string props, fires when data loads (no type).
They coexist because they fire at different moments. default="none" on both prevents cross-interference. Always pair enter with exit. Place directional VTs in page components, not layouts.
When a parent VT mounts/unmounts as one unit with nested VTs inside it, the nested ones do not fire their own enter/exit — only the outermost VT animates. (A child VT mounted inside a persistent parent VT fires enter/exit normally.) Per-item staggered animations during page navigation are not currently available in Next.js; see troubleshooting for the upstream experimental status.
For Next.js integration (transitionTypes on next/link and useRouter, App Router patterns, Server Components), see references/nextjs.md.
Include the reduced motion CSS from references/css-recipes.md as part of any view transition change the user approves. It is scoped to the view transition pseudo-elements. Tell the user which global stylesheet will change before writing to it.
For the complete guide with all reference files expanded: AGENTS.md (a compiled copy of this file and the reference files; it is guidance only and the same user confirmation rules apply).
Get started with chainctlchainctl skill install public/vercel-labs/react-view-transitions:latest
Bring Chainguard's hardening pipeline to your first-party skills — custom rulesets, automated remediation, full audit trail.
skills.cgr.dev/public/github.com/vercel-labs/skills/react-view-transitions:latest
MIT
AGENTS.md
HARDENING.md
README.md
SKILL.md
metadata.json
references/css-recipes.md
references/implementation.md
references/nextjs.md
references/patterns.md
references/troubleshooting.md