Subject of the issue

I don't know if what I'm doing is right but I am expecting the component to be attached in a div with an id of app but it's working as expected.

I provided a codesandbox to replicate my issue.

Steps to reproduce

Run the test.

Expected behaviour

The two logs of innerHTML of the body should have a parent of div with an id of app.

Actual behaviour

It attached the component on the directly in the body.

Possible Solution

What are the alternative solutions? Please describe what else you have considered?