Thanks for the fast reply,
After watching the video it explained exactly the error that is happening to me.
I have added the `.saveStyles()` method but still have the same error.
is it possible that I have the wrong syntax? I have tried:
here is my updated https://codesandbox.io/s/strange-firefly-5mtce?file=/src/App.js
ScrollTrigger.saveStyles("maskImageRef.current, contentRef.current")
and
ScrollTrigger.saveStyles([maskImageRef.current, contentRef.current])