Version

3.0.1

Reproduction link

https://codesandbox.io/s/vue3-render-bug-5h0yk?file=/src/App.vue

The reproduction is extract from my real-world project. It seems vNode is passed to key.

To make it rendered, you have multiple choices.

1. comment any of <outer /> or <x-button />
2. remove the empty object {} inside Button.vue's mixin
3. remove the wrapper <template /> in Inner.vue

Steps to reproduce

follow the link

What is expected?

it should render

What is actually happening?

error raised