Error occurs when using it with Vue.defineCustomElement

[kounetsuman]

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• Vue Version: 3.3.4
• Vue Select Version: 4.0.0-beta.6(npm, not cdn)
• Chrome: 115.0.5790.170
• node: v16.20.2

Describe the bug
A clear and concise description of what the bug is.

→An error occurs when using it with a custom element

Uncaught TypeError: Cannot read properties of undefined (reading 'header')
    at Proxy.ve (vue-select.es.js:656:189)
    at renderComponentRoot (runtime-core.esm-bundler.js:935:16)
    at ReactiveEffect.componentUpdateFn [as fn] (runtime-core.esm-bundler.js:5774:46)
    at ReactiveEffect.run (reactivity.esm-bundler.js:217:19)
    at instance.update (runtime-core.esm-bundler.js:5887:51)
    at setupRenderEffect (runtime-core.esm-bundler.js:5895:5)
    at mountComponent (runtime-core.esm-bundler.js:5685:5)
    at processComponent (runtime-core.esm-bundler.js:5638:9)
    at patch (runtime-core.esm-bundler.js:5126:11)
    at mountChildren (runtime-core.esm-bundler.js:5370:7)

Reproduction Link
A link to a reproduction of the bug. This is a huge help.

→ nothing

Steps To Reproduce
Outline the steps to reproduce the bug.

→Occurs with the following implementation

SelectItem.vue

<template>
  <v-select :options="options" />
</template>

<script setup>
import vSelect from 'vue-select';

const options = [
  { text: 'Option 1', value: 1 },
  { text: 'Option 2', value: 2 },
  { text: 'Option 3', value: 3 },
];
</script>

Parent.js

import SelectItem from './SelectItem.vue';

const element = defineCustomElement(SelectItem);
window.customElements.define('p-select-item', element);

index.html

<p-select-item></p-select-item>

Expected behavior
A clear and concise description of what you expected to happen.

→used in Vue.defineCustomElement

Screenshots
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→ nothing