Bug: profiler incorrectly reports 'The parent component rendered'

[michaelboyles]

React version: 19.0.0

Devtools version: 6.1.2 (5/7/2025)

Chrome: 136.0.7103.114

Windows 11

Steps To Reproduce

1. Go to this codesandbox link https://codesandbox.io/p/sandbox/optimistic-ritchie-forked-yhhjl4
2. Specifically open the preview in a new tab at https://yhhjl4.csb.app/ otherwise react devtools won't attach
3. Enable "Highlight updates when components render" in react dev tools
4. Click the numbered button to cause a rerender

Full code (click to show)

import { useState, useRef } from "react";

const Count = () => {
  const [count, setCount] = useState(0);
  return <button onClick={() => setCount((c) => c + 1)}>{count}</button>;
};

export function Greeting() {
  const renderCount = useRef(0);
  renderCount.current++;
  console.log("Greeting rendered");
  return <span>Hello World! (rendered {renderCount.current} times)</span>;
}

export default function App() {
  return (
    <div>
      <Count />
      <div>
        <Greeting />
      </div>
    </div>
  );
}

The current behavior

The Greeting component will flash as being rerendered even though it isn't

If you record via the profiler, the cause is given as "The parent component rendered", but it did not

The expected behavior

It neither flashes, nor is reported in the profiler flamegraph after being recorded. It didn't rerender.

---

Here's some variants I tested:

✅= Greeting correctly reported as not rerendering
❌ = Greeting incorrectly reported as rerendering

//✅ Same level
<Count />
<Greeting />

//✅ Greeting above
<div>
    <Greeting />
    <div><Count /></div>
</div>

// ❌ Greeting below in div
<Count />
<div>
    <Greeting />
</div>

// ❌ Greeting below in empty fragment 
<Count />
<>
    <Greeting />
</>

---

This is the same as #19732. Reopening here as per the directions in #19732 (comment)

[developerjhp]

I wasn’t fully certain about the intended direction of the issue, but I attempted a solution. Please let me know if any adjustments are needed. #33434

[hoxyq]

There is an issue with filtering out some elements. This data is probably not involved when we are determining if and why component re-rendered.

By default, React DevTools will filter out DOM-elements on Web. If you actually remove this filter from Components panel, it will correctly determine that these components were not re-rendered. Same for highlighting feature.

Screen.Recording.2025-06-13.at.16.27.11.mov

Would someone be interested in triaging this further? I can try helping with code links.