Is an included template always considered as sandboxed if the including template is sandboxed?

[ericmorand]

The documentation of the include function is not clear about the behaviour of the sandboxed parameter:

When including a template created by an end user, you should consider sandboxing it:

{{ include('page.html', sandboxed = true) }}

What happens in the following situation?

index.twig

{{ include('page.html', sandboxed = true) }}

page.html

{{ include('other.html', sandboxed = false) }}

Is other.html sandboxed - because the including template (page.html) is sandboxed - or is it not because the sandboxed argument is false?

In case it is, then what is the point of the sandboxed parameter?