[scoped-custom-element-registry] The scoped registry doesn't work if the DOM already contains the web component when it is defined.

[jpzwarte]

class Foo extends ScopedElementsMixin(LitElement) {
  static get scopedElements() {
    return { 'x-bar': Bar };
  }
}

0. Load the polyfill
1. Have <x-foo> in the DOM
2. Call customElements.define('x-foo', Foo);
3. window.customElements.get('x-bar') === Bar

Step 3 should be false, but is true.

If I remove <x-foo> from the DOM, then step 3 is false.

Also this only seems to happen with a production (rollup) build, not with a dev build :/ (specifically storybook build using vite build vs storybook dev)

Atm I only have time to report this and not create a reproduction :/