`<details>` element behaves incorrectly in Next.js 14/15

Link to the code that reproduces this issue

https://github.com/mikedidomizio/details-element-in-Next-14

To Reproduce

First sorry that the GitHub link is for Next14, it doesn't matter here

The <details> HTML element is an accordion style HTML tag that can show and hide information.

The onToggle event is expected to automatically fire on render if open is set to true Documentation

In the example above the event listener will be called once without any user interaction because the open attribute is set.

Below are CodeSandbox examples, the way to see if it automatically fire is to open the developer tools console and see that a console.log is either done or not.

In HTML it works that way ✅

In React 19 it works that way ✅

In React 18 it works that way ✅

In Next.js 15 it doesn't seem to work that way 🤔

In Next.js 14 it doesn't seem to work that way 🤔

So HTML/React will automatically trigger the onToggle event on render if open is set to true, but not Next.js.

Is this a bug or am I doing something wrong with the Next example?

(Originally posted on the Discord/Forum)

https://github.com/user-attachments/assets/f70b5f76-e31a-4072-8de8-35a6ace844f6

Current vs. Expected behavior

Current behaviour:

• Unles