vue3: $emit in mounted in new app results in TypeError: Cannot read property 'id' of undefined (timeline.js)

[ChristianBirkl]

Version

6.0.0-beta.11

Browser and OS info

Chrome 90 / Windows10

Steps to reproduce

create a new vue app with the following component:

<template>
  <div id="compA"></div>
  <input type="button" @click="createApp" value="+app" />
</template>
<script lang="ts">
import { defineComponent, createApp } from 'vue'

import CompA from "./components/CompA.vue";

export default defineComponent({
  methods: {
    createApp() {
      createApp(CompA).mount("#compA");
    }
  }
})
</script>

CompA.vue:

<template>
    <div></div>
</template>
<script lang="ts">
import { defineComponent } from 'vue'
export default defineComponent({
    mounted() {
        this.$emit("foo", "bar");
    }

})
</script>

Steps:

1. click +app

What is expected?

No error :-D

What is actually happening?

timeline.js:57 Uncaught (in promise) TypeError: Cannot read property 'id' of undefined
    at Object.<anonymous> (timeline.js:57)
    at Object.emit (<anonymous>:70:28)
    at devtoolsComponentEmit (runtime-core.esm-bundler.js:596)
    at emit (runtime-core.esm-bundler.js:969)
    at Configuration2.config.emitOptionChanged [as _emitOptionChanged] (configuration.js:271)
    at Configuration2._tryEmitOptionChanged (configuration.js:242)
    at Configuration2._onOptionChanged (configuration.js:228)
    at Configuration2.onOptionChanged (configuration.js:158)
    at Object.<anonymous> (component.js:136)
    at Object.Callback._fireCore (callbacks.js:25)

source:

global_hook_1.hook.on(shared_utils_1.HookEvents.COMPONENT_EMIT, async (app, instance, event, params) => {
    const appRecord = app_1.getAppRecord(app, ctx);

appRecord is undefined in this case.