Gsap Frameworks

Vue 3 (Composition API)

Use onMounted to run GSAP after the component is in the DOM. Use onUnmounted to clean up.

import { onMounted, onUnmounted, ref } from "vue";
import { gsap } from "gsap";
import { ScrollTrigger } from "gsap/ScrollTrigger";
gsap.registerPlugin(ScrollTrigger); // once per app, e.g. in main.js

export default {
  setup() {
    const container = ref(null);
    let ctx;

    onMounted(() => {
      if (!container.value) return;
      ctx = gsap.context(() => {
        gsap.to(".box", { x: 100, duration: 0.6 });
        gsap.from(".item", { autoAlpha: 0, y: 20, stagger: 0.1 });
      }, container.value);
    });

    onUnmounted(() => {
      ctx?.revert();
    });

    return { container };
  }
};

• ✅ gsap.context(scope) — pass the container ref (e.g. container.value) as the second argument so selectors like .item are scoped to that root. All animations and ScrollTriggers created inside the callback are tracked and reverted when ctx.revert() is called.
• ✅ onUnmounted — always call ctx.revert() so tweens and ScrollTriggers are killed and inline styles reverted.

Vue 3 (script setup)

Same idea with <script setup> and refs:

<script setup>
import { onMounted, onUnmounted, ref } from "vue";
import { gsap } from "gsap";
import { ScrollTrigger } from "gsap/ScrollTrigger";

const container = ref(null);
let ctx;

onMounted(() => {
  if (!container.value) return;
  ctx = gsap.context(() => {
    gsap.to(".box", { x: 100 });
    gsap.from(".item", { autoAlpha: 0, stagger: 0.1 });
  }, container.value);
});

onUnmounted(() => {
  ctx?.revert();
});
</script>

<template>
  <div ref="container">
    <div class="box">Box</div>
    <div class="item">Item</div>
  </div>
</template>

Svelte

Use onMount to run GSAP after the DOM is ready. Use the returned cleanup function from onMount (or track the context and clean up in a reactive block / component destroy) to revert. Svelte 5 uses a different lifecycle; the same principle applies: create in “mounted” and revert in “destroyed.”

<script>
  import { onMount } from "svelte";
  import { gsap } from "gsap";
  import { ScrollTrigger } from "gsap/ScrollTrigger";

  let container;

  onMount(() => {
    if (!container) return;
    const ctx = gsap.context(() => {
      gsap.to(".box", { x: 100 });
      gsap.from(".item", { autoAlpha: 0, stagger: 0.1 });
    }, container);
    return () => ctx.revert();
  });
</script>

<div bind:this={container}>
  <div class="box">Box</div>
  <div class="item">Item</div>
</div>

• ✅ bind:this={container} — get a reference to the root element so you can pass it to gsap.context(scope).
• ✅ return () => ctx.revert() — Svelte’s onMount can return a cleanup function; call ctx.revert() there so cleanup runs when the component is destroyed.

Scoping Selectors

Do not use global selectors that can match elements outside the current component. Always pass the scope (container element or ref) as the second argument to gsap.context(callback, scope) so that any selector run inside the callback is limited to that subtree.

• ✅ gsap.context(() => { gsap.to(".box", ...) }, containerRef) — .box is only searched inside containerRef.
• ❌ Running gsap.to(".box", ...) without a context scope in a component can affect other instances or the rest of the page.

ScrollTrigger Cleanup

ScrollTrigger instances are created when you use the scrollTrigger config on a tween/timeline or ScrollTrigger.create(). They are included in gsap.context() and reverted when you call ctx.revert(). So:

• Create ScrollTriggers inside the same gsap.context() callback you use for tweens.
• Call ScrollTrigger.refresh() after layout changes (e.g. after data loads) that affect trigger positions; in Vue/Svelte that often means after the DOM updates (e.g. nextTick in Vue, tick in Svelte, or after async content load).

When to Create vs Kill

Do not create GSAP animations in the component’s setup or in a synchronous top-level script that runs before the root element exists. Wait for onMounted / onMount (or equivalent) so the container ref is in the DOM.

Do Not

• ❌ Create tweens or ScrollTriggers before the component is mounted (e.g. in setup without onMounted); the DOM nodes may not exist yet.
• ❌ Use selector strings without a scope (pass the container to gsap.context() as the second argument) so selectors don’t match elements outside the component.
• ❌ Skip cleanup; always call ctx.revert() in onUnmounted / onMount’s return so animations and ScrollTriggers are killed when the component is destroyed.
• ❌ Register plugins inside a component body that runs every render (it doesn't hurt anything, it's just wasteful); register once at app level.

Learn More

• gsap-react skill for React-specific patterns (useGSAP, contextSafe).