Custom element render empty when recovered from KeepAlive

[ivan-94]

Vue version

3.0

Link to minimal reproduction

https://sfc.vuejs.org/#__DEV__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

Steps to reproduce

check the playround

What is expected?

render custom element content

What is actually happening?

empty

System Info

No response

Any additional comments?

call _update when connectedCallback invoked

https://github.dev/vuejs/core/blob/b0b74a160c08941fa9a7a5460f36a1f2fccbf423/packages/runtime-dom/src/apiCustomElement.ts#L179