Incorrect custom element tag name in innerHTML

[bavoco]

Describe the bug
The output of a custom element tagname in innerHTML is null.

To Reproduce

// repro.js
import { Window } from "happy-dom";

const win = new Window();

class myCustomElement extends win.HTMLElement {}
win.customElements.define("my-custom-element", myCustomElement);

win.document.body.append(new myCustomElement());
console.log(win.document.body.innerHTML);

Running node repro.js outputs:

<null></null>

Expected behavior

<my-custom-element></my-custom-element>

Version:

• Happy-dom: 14.3.3
• Node: 21.5.0

Additional context
Interestingly console.log(win.document.body.firstChild.tagName) outputs MY-CUSTOM-ELEMENT

[capricorn86]

Thank you for reporting @bavoco! 🙂

There is a fix in now:
https://github.com/capricorn86/happy-dom/releases/tag/v14.3.5