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I'm just starting out with React and `useGSAP` and I'm running into an issue with out what appears to be the hook registering: react.development.js:1630 Uncaught TypeError: Cannot read properties of null (reading 'useRef') at useRef (react.development.js:1630:1) at useGSAP (index.js:32:1) However, despite this error - I can console.log the `useGSAP` hook, and also the `gsap` package and both are successfully loaded. This error message happens when I try to use useGSAP. This is the error message i'm getting: Segment.tsx:39 Warning: Invalid hook call. Hooks can only be called inside of the body of a function component. This could happen for one of the following reasons: 1. You might have mismatching versions of React and the renderer (such as React DOM) 2. You might be breaking the Rules of Hooks 3. You might have more than one copy of React in the same app See https://reactjs.org/link/invalid-hook-call for tips about how to debug and fix this problem. printWarning @ react.development.js:209 error @ react.development.js:183 resolveDispatcher @ react.development.js:1592 useRef @ react.development.js:1629 useGSAP @ index.js:32 (anonymous) @ Segment.tsx:39 react.development.js:1630 Uncaught TypeError: Cannot read properties of null (reading 'useRef') at useRef (react.development.js:1630:1) at useGSAP (index.js:32:1) at Segment.tsx:39:1 at renderWithHooks (react-dom.development.js:16305:1) at updateForwardRef (react-dom.development.js:19226:1) at beginWork (react-dom.development.js:21636:1) at HTMLUnknownElement.callCallback (react-dom.development.js:4164:1) at Object.invokeGuardedCallbackDev (react-dom.development.js:4213:1) at invokeGuardedCallback (react-dom.development.js:4277:1) at beginWork$1 (react-dom.development.js:27451:1) here's what i have so far: import React, { forwardRef, useEffect, useCallback, useRef } from "react"; import { useActiveSegment, BkExpeditionContextValues, } from "src/BkExpedition/index"; import { mergeRefs } from "src/util/mergRefs"; import clsx from "clsx"; import gsap from "gsap/dist/gsap"; import { useGSAP } from "@gsap/react"; gsap.registerPlugin(useGSAP); export type SegmentProps = Omit< React.ComponentPropsWithoutRef<"section">, "onAnimationStart" | "onDragStart" | "onDragEnd" | "onDrag" | "onDragOver" > & { segmentKey: BkExpeditionContextValues["activeSegment"]; }; export const Segment = forwardRef<HTMLDivElement, SegmentProps>( (props, ref) => { const { segmentKey, className, children, ...restOfHtmlAttrs } = props; const { activeSegment, previousSegment } = useActiveSegment(); const isActive = activeSegment === segmentKey; const sectionRef = useRef<HTMLDivElement>(null); const animateInTL = useRef<gsap.core.Timeline>(); const animateOutTL = useRef<gsap.core.Timeline>(); useGSAP(() => { // console.log("sectionRef", sectionRef.current); // if (sectionRef.current === null) return; // // animateInTL.current = gsap // .timeline({ paused: true }) // .fromTo(sectionRef?.current, { x: "100%" }, { x: "0%" }); // animateOutTL.current = gsap // .timeline({ paused: true }) // .fromTo(sectionRef?.current, { x: "0%" }, { x: "-100%" }); }); useEffect(() => { if (previousSegment === null) { return; } if (activeSegment === segmentKey) { animateInTL?.current?.play(); return; } if (previousSegment === segmentKey) { animateOutTL?.current?.play(); return; } }, [activeSegment, previousSegment, segmentKey]); return ( <section ref={mergeRefs(ref, sectionRef)} {...restOfHtmlAttrs} aria-hidden={!isActive} className={clsx(className, styles.segment, isActive && styles.isActive)} style={{ transform: isActive ? "translateX(0%)" : "translateX(100%)", }} > {children} </section> ); }, ); Segment.displayName = "Segment"; Am i not registering the book in the right place? Should it be registered inside the function component? FWIW - I plan to use this component in Next.js. Any help would be really appreciated -Gabriel

I put an <a> tag for project on the navbar, as I click "project" it will scroll me to the section by its id. I wonder if this function conflicts with scrolltrigger function causing the issue or not. I have a few React components on the top of this project component. import "./Project.scss" import ProjectList from "./ProjectList/ProjectList" import { projectdata } from "./ProjectData.js" import { useEffect, useRef } from "react"; import { gsap } from "gsap/all"; import { ScrollTrigger } from "gsap/ScrollTrigger" export default function Project() { gsap.registerPlugin(ScrollTrigger); const listRef = useRef(null); useEffect(() => { gsap.fromTo(listRef.current, { y: "100%", opacity: 0 }, { y: "0%", opacity: 1, duration: 2, scrollTrigger: { trigger: listRef.current, markers: true, }, }); }) return ( <div className='project' id='project'> <h1>Project</h1> <ul> {projectdata.map((project, index) => ( <ProjectList {...project} key={index} ref={listRef} /> ))} </ul> </div> ) }

Hi there, I am running into an odd issue with my React site and using GSAP. Website: https://gpstaging.netlify.app For all the scroll based triggers, if I resize the window they will either disappear https://take.ms/6VGoD or not fire their animation when scrolling down the page. It looks like they disappear because an inline style of opacity: 0 and visibility: none is getting applied to them. But I have no idea why and even when I removed all the other components that had GSAP animation applied, the styles keep showing up. Here is a simplified demonstration of the items disappearing once the window get's resized a few times. https://codesandbox.io/s/festive-feistel-puiib?file=/src/App.js For the full production code version, please see the below Github link. https://github.com/GedalyaKrycer/gedalyakrycer.github.io/blob/gsapBackup/gk-portfolio/src/components/Bio/index.js I suspect I am not using the useRef correctly and maybe there is issues with having multiple components that have GSAP on it. But I am not sure how to troubleshoot it. Much appreciation for any insight. Gedalya