private fields broken in specific case

### Link to the code that reproduces this issue https://codesandbox.io/p/devbox/cool-yalow-zzkp58 ### To Reproduce Click preview Wait for it to hydrate It throws an error: "attempted to get private field on non-instance" ### Current vs. Expected behavior Here is the same code running in react without Next.js: [https://codesandbox.io/p/sandbox/tslrlg](https://codesandbox.io/p/sandbox/tslrlg) The getter does not throw and returns the value of the private field. In the broken Next.js version, it renders fine on the server side, but when it rehydrates it throws. The bug only happens if all of these are true: - using Next.js - a function is imported from another file - that looks like this: `() => new class ClassName {/* class body */}` - the returned instance is passed through useMemo or useRef The following function formats do not trigger the error: - `() => { return new class ClassName {/* class body */} }` - `() => new ClassName()` - `() => instance` - exporting the class constructor ```js "use client"; import { useRef } from "react"; import { construct } from "./construct"; export default function Home() { const a = construct() const ref = useRef(a); const b = ref.current; return b.test; // throws client-side } ``` ```js export const construct = () => new class { #test = 99 get test() { return this.#test } } ``` ### Provide environment information ```bash It's running on CodeSandbox ``` ### Which area(s) are affected? (Select all that apply) Runtime ### Which stage(s) are affected? (Select all that apply) next dev (local)