Vue version

3.5.17

Link to minimal reproduction

https://play.vuejs.org/#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

Steps to reproduce

I want to expose component method as custom element method.

What is expected?

Method inc should be accessible from DOM.

What is actually happening?

Method inc is not available.

It seems that you are not able to iterate over reactive object exposed inside mount hook.

This loop seems not to work:
https://github.com/vuejs/core/blob/main/packages/runtime-dom/src/apiCustomElement.ts#L433

System Info

Any additional comments?

No response